A335423 - OEIS

%I #6 Jun 13 2020 22:09:57

%S 1,2,3,1,5,4,7,2,1,6,11,3,13,10,9,1,17,2,19,5,15,14,23,4,1,22,3,7,29,

%T 8,31,2,21,26,25,1,37,34,33,6,41,12,43,11,5,38,47,3,1,2,39,13,53,4,35,

%U 10,51,46,59,9,61,58,7,1,55,20,67,17,57,18,71,2,73,62,3,19,49,28,79,5,1,74,83,15,65,82,69,14,89,6

%N a(n) = A005940(1+A248663(n)).

%H Antti Karttunen, <a href="/A335423/b335423.txt">Table of n, a(n) for n = 1..16384</a>

%F a(n) = A005940(1+A248663(n)) = A005940(1+A048675(A007913(n))).

%o (PARI)

%o A048675(n) = { my(f = factor(n)); sum(k=1, #f~, f[k, 2]*2^primepi(f[k, 1]))/2; };

%o A248663(n) = A048675(core(n));

%o A005940(n) = { my(p=2, t=1); n--; until(!n\=2, if((n%2), (t*=p), p=nextprime(p+1))); t };

%o A335423(n) = A005940(1+A248663(n));

%Y Cf. A005940, A007913, A048675, A248663, A335424, A335425.

%K nonn

%O 1,2

%A _Antti Karttunen_, Jun 13 2020