回答編集履歴
1
d
test
CHANGED
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@@ -2,7 +2,7 @@
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2
2
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3
3
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4
4
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5
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-
## for
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5
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## for で計算する。
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6
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7
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8
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@@ -55,3 +55,67 @@
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55
55
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print(array)
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56
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57
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```
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58
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59
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60
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61
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## 一般項
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62
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63
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64
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65
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```
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66
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67
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a_{n + 1} = 2 * a_n + 3
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68
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```
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70
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72
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の一般項は
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74
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75
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```
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78
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79
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a_n = 4 * 2^{n - 1} - 3
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81
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```
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82
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83
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84
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85
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なので、
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86
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87
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88
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89
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```python
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90
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def a(n):
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92
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93
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return 4 * 2 ** (n - 1) - 3
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94
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95
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96
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array = []
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99
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for i in range(1, N + 1):
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100
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array.append(a(i))
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102
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103
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```
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104
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105
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106
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107
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もしくは numpy で一発で以下のように計算してもよいかと思います。
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108
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109
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110
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111
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```python
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112
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113
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def a(n):
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114
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115
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return 4 * 2 ** (n - 1) - 3
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116
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117
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118
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119
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array = a(np.arange(1, N + 1))
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120
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121
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```
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