A331267 a(n) is the greatest divisor v of A331219(n) such that the binary representations of v and of A331219(n)/v have the same number of 0's and the same number of 1's.

1, 2, 3, 4, 5, 6, 6, 7, 8, 9, 10, 10, 12, 12, 11, 13, 12, 14, 13, 14, 14, 15, 16, 17, 18, 18, 20, 20, 19, 21, 20, 24, 22, 24, 21, 22, 25, 24, 22, 26, 25, 23, 28, 26, 25, 26, 24, 28, 28, 27, 25, 26, 29, 26, 30, 28, 28, 27, 29, 28, 30, 29, 30, 30, 31, 32, 33, 34

Offset

1,2

Links

Rémy Sigrist, Table of n, a(n) for n = 1..10000

Rémy Sigrist, Scatterplot of (n, a(n)-A331266(n)) for n = 1..32529

Formula

a(n) * A331266(n) = A331219(n).

Prog

(PARI) b=2; k=68; for (n=1, oo, fordiv (n, u, if (vecsort(digits(u, b))==vecsort(digits(v=n/u, b)), print1 (v", "); break (if (k--, 1, 2)))))

Crossrefs

Cf. A331219, A331266.

Sequence in context: A340767 A099848 A082287 * A238839 A269169 A248148

Adjacent sequences: A331264 A331265 A331266 * A331268 A331269 A331270

Keyword

nonn,base

Author

Rémy Sigrist, Jan 13 2020

Status

approved