A344999 - OEIS

%I #6 Jun 07 2021 06:50:00

%S -1,0,-4,9,-18,60,-40,33,4,90,-108,240,-154,120,48,93,-270,288,-340,

%T 468,0,180,-504,672,-54,210,52,768,-810,3096,-928,237,-192,270,-480,

%U 948,-1330,300,-336,1404,-1638,5088,-1804,1584,648,360,-2160,1680,-216,684,-720,2100,-2754,1116,-1584,2400,-960,450,-3420,10080

%N a(n) = A048250(n) * A345001(n).

%F a(n) = A048250(n) * A345001(n).

%F a(n) = A344998(n) - A345043(n).

%o (PARI)

%o A003415(n) = if(n<=1, 0, my(f=factor(n)); n*sum(i=1, #f~, f[i, 2]/f[i, 1]));

%o A048250(n) = factorback(apply(p -> p+1,factor(n)[,1]));

%o A345001(n) = (sigma(n)+A003415(n)-(2*n));

%o A344999(n) = (A048250(n) * A345001(n));

%Y Cf. A000203, A003415, A048250, A345001.

%Y Cf. A345003 [gives k for which a(k) = A344998(k)], A345004, A345005.

%K sign

%O 1,3

%A _Antti Karttunen_, Jun 05 2021