A336944 Numbers k that have at least two different representations as the product of a number and of its decimal digits.

0, 192, 648, 819, 1197, 1536, 4872, 4977, 5976, 7056, 9968, 13608, 20448, 21168, 22176, 22428, 22752, 32040, 33984, 35424, 36864, 37692, 38736, 59778, 64152, 77600, 89928, 96912, 112833, 112896, 113148, 116352, 116736, 120384, 120708, 146412, 154752, 156288, 192888

Offset

1,2

Comments

Subsequence of A336826.

Links

Chai Wah Wu, Table of n, a(n) for n = 1..10000 (n = 1..500 from Seiichi Manyama)

Example

192 = 24 * (2*4) = 32 * (3*2).
549504 = 1696 * (1*6*9*6) = 2862 * (2*8*6*2) = 3392 * (3*3*9*2) = 3816 * (3*8*1*6).
1798848 = 6246 * (6*2*4*6) = 12492 * (1*2*4*9*2) = 33312 * (3*3*3*1*2).

Mathematica

digprod[n_] := n * Times @@ IntegerDigits[n]; seqQ[0] = True; seqQ[n_] := DivisorSum[n, Boole[digprod[#] == n] &] > 1; Select[Range[0, 2 * 10^5], seqQ] (* Amiram Eldar, Aug 08 2020 *)

Crossrefs

Cf. A098736, A336826, A336876.

Sequence in context: A254854 A254847 A251083 * A194647 A054001 A051527

Adjacent sequences: A336941 A336942 A336943 * A336945 A336946 A336947

Keyword

nonn,base

Author

Seiichi Manyama, Aug 08 2020

Status

approved