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A324716
a(n) = 2*A156552(n) - bitand(2*A156552(n), A323243(n)), where bitand is bitwise-AND, A004198.
4
0, 2, 4, 2, 8, 8, 16, 6, 0, 18, 32, 18, 64, 32, 4, 6, 128, 16, 256, 34, 0, 66, 512, 38, 0, 130, 4, 70, 1024, 10, 2048, 30, 64, 258, 0, 22, 4096, 512, 4, 70, 8192, 72, 16384, 130, 8, 1026, 32768, 78, 0, 32, 256, 258, 65536, 32, 0, 134, 4, 2048, 131072, 82, 262144, 4098, 64, 22, 128, 138, 524288, 518, 1024, 80, 1048576, 38, 2097152, 8194, 20, 1030, 0, 266
OFFSET
1,2
COMMENTS
Equivalently, a(n) = 2*A156552(n) XOR (2*A156552(n) AND A323243(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
A324716(n) = { my(t=2*A156552(n)); bitxor(t, bitand(t, A323243(n))); };
\\ Or equivalently:
A324716(n) = { my(t=2*A156552(n)); t - bitand(t, A323243(n)); };
CROSSREFS
Cf. A003987, A004198, A156552, A323243, A324717, A324722 (positions of zeros).
Sequence in context: A304213 A129178 A152874 * A328378 A296429 A065286
KEYWORD
nonn
AUTHOR
Antti Karttunen, Mar 15 2019
STATUS
approved