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A372840 a(n) = 5-adic valuation of A008336(5*n).

%I A372840 #13 Jun 03 2024 18:32:09
%S A372840 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,
%T A372840 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,
%U A372840 1,2,0,1,0,1,0,3,4,3,2,1,3,2,1,0,1,3,2
%N A372840 a(n) = 5-adic valuation of A008336(5*n).
%H A372840 Michael De Vlieger, <a href="/A372840/b372840.txt">Table of n, a(n) for n = 1..10000</a>
%F A372840 a(n) = A112765(A008336(5*n)).
%t A372840 k = 3; nn = 600; p[_] := 0; r = 0; q = Prime[k];
%t A372840 {0}~Join~Reap[
%t A372840     Do[If[AnyTrue[#, p[#1] < #2 & @@ # &],
%t A372840         Map[p[#1] += #2 & @@ # &, #],
%t A372840         Map[p[#1] -= #2 & @@ # &, #] ] &@
%t A372840         Map[{PrimePi[#1], #2} & @@ # &, FactorInteger[n]];
%t A372840       If[Divisible[n, q], Sow[p[k] ] ], {n, nn}] ][[-1, 1]]
%Y A372840 Cf. A008336, A112765, A371908, A372095.
%K A372840 nonn,easy
%O A372840 1,6
%A A372840 _Michael De Vlieger_, Jun 02 2024