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A295907
a(n) = SumXOR_{k=1..n} A296099(k), where SumXOR is the analog of summation under the binary XOR operation.
2
1, 2, 0, 4, 15, 6, 0, 8, 27, 30, 11, 12, 0, 14, 30, 0, 17, 54, 57, 20, 0, 22, 46, 0, 25, 78, 81, 112, 58, 30, 62, 0, 66, 34, 0, 72, 37, 0, 78, 120, 82, 126, 86, 0, 90, 46, 94, 0, 49, 100, 0, 52, 159, 162, 220, 224, 171, 232, 177, 240, 183, 186, 252, 128, 0
OFFSET
1,2
COMMENTS
For any n > 0, a(n) is divisible by n.
For any n > 0, if a(n) = 0, then A296099(n+1) is a multiple of n+1.
EXAMPLE
a(3) = A296099(1) XOR A296099(2) XOR A296099(3) = 1 XOR 3 XOR 2 = 0.
PROG
(PARI) s = 0; x = 0; for (n=1, 65, for (k=1, oo, if (!bittest(s, k) && (xx=bitxor(x, k))%n==0, x = xx; s += 2^k; print1 (x ", "); break)))
CROSSREFS
Cf. A296099.
Sequence in context: A343472 A214199 A320491 * A317364 A265664 A320490
KEYWORD
nonn,base
AUTHOR
Rémy Sigrist, Dec 05 2017
STATUS
approved