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A324816
Binary weight of A324815; number of 1-bits in common positions in 2*A156552(n) and A323243(n).
3
0, 0, 0, 1, 0, 1, 0, 1, 2, 0, 0, 1, 0, 1, 1, 2, 0, 2, 0, 1, 2, 0, 0, 1, 2, 0, 2, 0, 0, 1, 0, 1, 1, 0, 2, 1, 0, 1, 1, 1, 0, 1, 0, 1, 2, 0, 0, 1, 2, 2, 1, 1, 0, 3, 2, 1, 1, 1, 0, 1, 0, 0, 2, 3, 1, 0, 0, 0, 1, 1, 0, 2, 0, 0, 1, 0, 2, 0, 0, 1, 1, 0, 0, 2, 1, 0, 1, 0, 0, 3, 1, 0, 0, 0, 2, 3, 0, 1, 1, 1, 0, 1, 0, 1, 1
OFFSET
1,9
COMMENTS
Numbers 0 .. 7 occur for the first time in 1, 4, 9, 54, 162, 972, 2816, 3456. These are also the positions of records so far.
FORMULA
a(n) = A000120(A324815(n)).
a(p) = 0 for all primes p.
a(A324201(n)) = A000043(n).
PROG
(PARI)
A156552(n) = {my(f = factor(n), 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 by David A. Corneth
A324816(n) = hammingweight(bitand(2*A156552(n), A323243(n))); \\ Needs code also from A323243.
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Mar 17 2019
STATUS
approved