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A336854
a(n) = A336841(n)/2.
2
0, 1, 2, 7, 3, 18, 5, 34, 22, 26, 6, 96, 8, 42, 46, 142, 9, 163, 11, 137, 74, 50, 14, 420, 45, 66, 172, 219, 15, 324, 18, 547, 88, 74, 106, 811, 20, 90, 116, 596, 21, 516, 23, 260, 401, 114, 26, 1662, 115, 327, 130, 342, 29, 1188, 126, 948, 158, 122, 30, 1578, 33, 146, 639, 2005, 166, 612, 35, 383, 200, 732, 36, 3430
OFFSET
1,3
FORMULA
a(n) = Sum_{d|n} (A048673(n)-A048673(d)).
PROG
(PARI)
A003961(n) = { my(f = factor(n)); for(i=1, #f~, f[i, 1] = nextprime(f[i, 1]+1)); factorback(f); };
A336854(n) = { my(s=A003961(n)); sumdiv(s, d, (s-d))/2; };
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Aug 08 2020
STATUS
approved