A331270 a(n) is the least divisor u of A331221(n) such that the decimal representations of u and of A331221(n)/u have the same number of digits d for d = 0..9.

1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 12, 16, 17, 18, 19, 20, 13, 21, 22, 23, 14, 24, 25, 26, 27, 23, 15, 28, 29, 30, 31, 16, 24, 32, 33, 34, 17, 35, 36, 25, 37, 38, 18, 34, 39, 40, 26, 41, 19, 42, 43, 35, 44, 27, 45, 46, 47, 36, 28, 48, 49, 45

Offset

1,2

Links

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

Formula

a(n) * A331271(n) = A331221(n).

Prog

(PARI) b=10; k=67; for (n=1, oo, fordiv (n, u, if (vecsort(digits(u, b))==vecsort(digits(n/u, b)), print1 (u", "); break (if (k--, 1, 2)))))

Crossrefs

Cf. A331221, A331271.

Sequence in context: A366994 A365683 A057946 * A117657 A352529 A357434

Adjacent sequences: A331267 A331268 A331269 * A331271 A331272 A331273

Keyword

nonn,base

Author

Rémy Sigrist, Jan 13 2020

Status

approved