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A324819
a(n) = 2*A156552(n) OR A323243(n), where OR is bitwise-OR, A003986.
5
0, 3, 7, 6, 15, 14, 31, 14, 12, 31, 63, 30, 127, 50, 22, 30, 255, 30, 511, 54, 39, 114, 1023, 62, 28, 214, 28, 118, 2047, 42, 4095, 62, 118, 434, 42, 62, 8191, 770, 148, 126, 16383, 110, 32767, 198, 44, 1826, 65535, 126, 60, 63, 508, 390, 131071, 62, 91, 206, 532, 3350, 262143, 126, 524287, 6834, 124, 126, 254, 234, 1048575, 822
OFFSET
1,2
FORMULA
a(A000040(n)) = A000225(1+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
A324819(n) = bitor(2*A156552(n), A323243(n)); \\ Needs code also from A323243.
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Mar 18 2019
STATUS
approved