A249072 - OEIS

%I #7 Oct 26 2014 20:48:35

%S 0,1,0,1,1,2,0,2,1,2,2,2,3,0,2,3,1,3,2,4,0,3,2,3,3,3,4,1,3,3,4,2,4,2,

%T 4,3,4,3,5,0,3,4,4,3,6,0,4,4,4,5,1,4,4,6,1,3,5,2,5,2,4,5,3,5,3,4,5,4,

%U 4,7,0,3,7,1,4,5,3,5,4,8,0,4,5,4,6,2,6,2,5,5,4,6,3,8,1,4,9,0

%N Sum of prime indices in the prime factorization of A249337(n), counted with multiplicity: a(n) = A056239(A249337(n)).

%H Antti Karttunen, <a href="/A249072/b249072.txt">Table of n, a(n) for n = 1..12580</a>

%F a(n) = A056239(A249337(n)).

%o (PARI)

%o A049084(n) = if(isprime(n), primepi(n), 0); \\ This function from _Charles R Greathouse IV_

%o A056239(n) = { my(f); if(1==n, 0, f=factor(n); sum(i=1, #f~, f[i,2] * A049084(f[i,1]))); }

%o A249072_write_bfile(up_to_n) = { my(counts, n, a_k, a_n); counts = vector(up_to_n); a_k = 1; for(n = 1, up_to_n, a_n = A056239(a_k); write("b249072_upto12580.txt", n, " ", a_n); counts[1+a_n]++; if(1 == n, a_k = 2, a_k = counts[1+a_n])); };

%o A249072_write_bfile(12580);

%o (Scheme) (define (A249072 n) (A056239 (A249337 n)))

%Y Cf. A056239, A249337, A249338.

%Y Cf. A249341 (positions of zeros), A249342 (positions of records).

%K nonn

%O 1,6

%A _Antti Karttunen_, Oct 26 2014