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A347876
a(n) = A323905(sigma(n)), where A323905(x) = A156552(x) - A048675(x).
2
0, 0, 1, 0, 2, 7, 4, 4, 0, 8, 7, 25, 8, 18, 18, 0, 8, 32, 13, 26, 26, 21, 18, 35, 0, 26, 32, 60, 14, 48, 26, 26, 41, 22, 41, 32, 128, 35, 60, 36, 26, 88, 49, 63, 98, 48, 41, 3073, 128, 1024, 48, 32, 22, 78, 48, 78, 71, 36, 35, 138, 1024, 88, 228, 0, 63, 103, 193, 64, 88, 103, 48, 100, 2048, 386, 3073, 69, 88, 138, 71
OFFSET
1,5
FORMULA
a(n) = A323905(A000203(n)).
a(n) = A332221(n) - A331750(n).
PROG
(PARI)
A048675(n) = { my(f = factor(n)); sum(k=1, #f~, f[k, 2]*2^primepi(f[k, 1]))/2; }; \\ From A048675
A156552(n) = {my(f = factor(n), p, p2 = 1, res = 0); for(i = 1, #f~, p = 1 << (primepi(f[i, 1]) - 1); res += (p * p2 * (2^(f[i, 2]) - 1)); p2 <<= f[i, 2]); res}; \\ From A156552
A323905(n) = (A156552(n) - A048675(n));
A347876(n) = A323905(sigma(n));
KEYWORD
nonn
AUTHOR
Antti Karttunen, Sep 19 2021
STATUS
approved