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A258848
The n-th pi-based arithmetic derivative of 2^3.
2
8, 12, 20, 32, 80, 208, 512, 2304, 12288, 81920, 622592, 4931584, 38944768, 278380544, 2122727424, 17483677696, 128412352512, 1348723408896, 14768867966976, 188484960780288, 2416519442792448, 30543291749302272, 375877192068366336, 6101345960934506496
OFFSET
0,1
FORMULA
a(n) = A258851^n(2^3).
MAPLE
with(numtheory):
d:= n-> n*add(i[2]*pi(i[1])/i[1], i=ifactors(n)[2]):
a:= proc(n) option remember; `if`(n=0, 2^3, d(a(n-1))) end:
seq(a(n), n=0..23);
CROSSREFS
Row n=8 of A258850.
Sequence in context: A211410 A001749 A175786 * A072843 A354069 A350615
KEYWORD
nonn
AUTHOR
Alois P. Heinz, Jun 12 2015
STATUS
approved