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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 (list; graph; refs; listen; history; text; internal format)
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.
LINKS
Antti Karttunen, Table of n, a(n) for n = 1..10000 (based on Hans Havermann's factorization of A156552)
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
Sequence in context: A324868 A363622 A287066 * A321448 A334158 A116357
KEYWORD
nonn
AUTHOR
Antti Karttunen, Mar 17 2019
STATUS
approved

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Last modified August 31 15:16 EDT 2024. Contains 375572 sequences. (Running on oeis4.)