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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.
3
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
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
Sequence in context: A340767 A099848 A082287 * A238839 A269169 A248148
KEYWORD
nonn,base
AUTHOR
Rémy Sigrist, Jan 13 2020
STATUS
approved