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A369638
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The n-th arithmetic derivative of 2^7.
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3
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128, 448, 1408, 5056, 15232, 56384, 169216, 677120, 2902784, 12008192, 49750016, 323383296, 2048106496, 13312700416, 79908855808, 520115646464, 3120693882880, 19851642843136, 121321447460864, 754017659596800, 5330629212856320, 37592273278603264, 230970707522453504, 1736195064174952448, 12244744136813133824
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OFFSET
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0,1
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COMMENTS
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Iterates of the map k -> k', starting from k=128, where k' stands for the arithmetic derivative, A003415.
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LINKS
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FORMULA
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a(0) = 128, and for n > 0, a(n) = A003415(a(n-1)).
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PROG
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(PARI)
A003415(n) = if(n<=1, 0, my(f=factor(n)); n*sum(i=1, #f~, f[i, 2]/f[i, 1]));
(PARI)
up_to = 89;
A003415(n) = if(n<=1, 0, my(f=factor(n)); n*sum(i=1, #f~, f[i, 2]/f[i, 1]));
A369638list(up_to) = { my(v=vector(up_to)); v[1] = 128;
for(i=2, up_to, print1(i, ", "); v[i] = A003415(v[i-1])); (v); };
v369638 = A369638list(1+up_to);
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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