A374216 - OEIS

%I #6 Jul 02 2024 18:47:13

%S 1,0,2,0,0,0,1,1,0,0,0,0,0,3,3,0,3,0,0,1,0,0,0,1,0,0,0,0,1,0,1,1,0,2,

%T 1,0,0,4,0,0,2,0,0,0,0,0,0,1,2,2,0,0,0,4,0,1,0,0,2,0,0,0,2,1,4,0,0,1,

%U 1,0,2,0,0,0,0,1,1,0,0,2,0,0,1,1,0,5,0,0,0,2,0,1,0,3,0,0,4,0,1,0,1,0,0,0,0,0,0,0,1,3,0,0,3,2,0,0,0,3,1,1

%N The 2-adic valuation of sopfr(n), where sopfr is the sum of prime factors with repetition, A001414.

%H Antti Karttunen, <a href="/A374216/b374216.txt">Table of n, a(n) for n = 2..100000</a>

%F a(n) = A007814(A001414(n)).

%o (PARI)

%o A001414(n) = ((n=factor(n))[, 1]~*n[, 2]);

%o A374216(n) = valuation(A001414(n), 2);

%Y Cf. A001414, A007814, A036349 (gives the indices of nonzero terms here, after its initial 1), A335657 (gives the indices of 0's), A356163.

%Y Cf. also A374206, A374217.

%K nonn

%O 2,3

%A _Antti Karttunen_, Jul 02 2024