A126789 -id:A126789 - cp's OEIS frontend

A176623 A126789 with zeros removed.

1, 36, 66, 88, 257, 268, 279, 448, 369, 459, 666, 578, 579, 678, 1689, 2558, 789, 1899, 13557, 999, 3477, 2589, 2688, 13578, 3489, 3588, 2799, 4569, 4668, 4677, 5568, 3699, 3789, 4599, 14779, 4689, 5679, 4789, 25566, 5788, 6679, 6778, 34566, 5889, 117788, 25569, 33579

Offset: 1

Michel Lagneau, Apr 22 2010

Also smallest k such that product of digits of k equals n times sum of digits of k, i.e. smallest k such that A007954(k) = n * A007953(k). - David A. Corneth, Jul 23 2025

			a(45) = 117788 as A002473(45) = 98 and the smallest positive integer that has product of digit = 98*sum of digits is 117788. - _David A. Corneth_, Jul 23 2025

David A. Corneth, Table of n, a(n) for n = 1..10000

Cf. A007953, A007954, A062035, A062036, A062037, A062382.

a(45)-a(47) from David A. Corneth, Jul 23 2025

A319507 Smallest number of multiplicative-additive divisors persistence n.

Original entry on oeis.org

1, 2, 36, 3489, 24778899, 566677899999, 47777778999999999999

Offset: 0

Pieter Post, Sep 21 2018

To compute the "multiplicative-additive divisors persistence" of a number, we proceed as follows. Form the product of the digits of the number (A007954) divided by the sum of the digits (A007953). Repeat this process until you reach 0 or 1. If we reach a non-integer, we write 0. The "multiplicative-additive divisors persistence" is the number of steps to reach 0 or 1.

For instance: the multiplicative-additive divisors persistence of 874 is 1, because 874 -> 8 * 7 * 4 / (8 + 7 + 4) = 224/19. This is not an integer, so the process stops after one step.

			The multiplicative additive divisors persistence of 24778899 is 4: 24778899 -> (2032128/54=) 37632 -> (756/21=) 36 -> (18/9=) 2 -> (2/2=) 1.

Cf. A038367, A126789, A003001, A006050, A007953, A007954, A031346.

Offset set to 0. - R. J. Mathar, Jun 30 2020

cp's OEIS Frontend

A176623 A126789 with zeros removed.

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