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A372840
a(n) = 5-adic valuation of A008336(5*n).
3
0, 1, 0, 1, 0, 2, 1, 2, 3, 2, 0, 1, 0, 1, 0, 2, 3, 4, 3, 2, 0, 1, 0, 1, 2, 5, 4, 3, 4, 5, 3, 4, 5, 4, 3, 1, 0, 1, 0, 1, 3, 4, 3, 4, 5, 3, 2, 1, 2, 3, 0, 1, 0, 1, 0, 2, 3, 4, 3, 4, 2, 3, 2, 3, 4, 2, 1, 0, 1, 2, 0, 1, 0, 1, 0, 3, 4, 3, 2, 1, 3, 2, 1, 0, 1, 3, 2
OFFSET
1,6
LINKS
FORMULA
a(n) = A112765(A008336(5*n)).
MATHEMATICA
k = 3; nn = 600; p[_] := 0; r = 0; q = Prime[k];
{0}~Join~Reap[
Do[If[AnyTrue[#, p[#1] < #2 & @@ # &],
Map[p[#1] += #2 & @@ # &, #],
Map[p[#1] -= #2 & @@ # &, #] ] &@
Map[{PrimePi[#1], #2} & @@ # &, FactorInteger[n]];
If[Divisible[n, q], Sow[p[k] ] ], {n, nn}] ][[-1, 1]]
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Michael De Vlieger, Jun 02 2024
STATUS
approved