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A341433 Numbers that are divisible by the product of their digits in primorial base representation. 1
1, 3, 9, 21, 39, 51, 99, 249, 261, 309, 669, 729, 2559, 2571, 2619, 2979, 3051, 4239, 7179, 7191, 32589, 32601, 32649, 32661, 33009, 33021, 37209, 37269, 37629, 51489, 92649, 92709, 93069, 97281, 272889, 274509, 543099, 543111, 543159, 543519, 543591, 544779 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

The primorial base repunits (A143293) are all terms since their product of digits in primorial base is 1.

All the terms are zeroless in primorial base, and therefore they are terms of A328574. In particular, since the last digit of even numbers in primorial base is 0, all the terms are odd numbers.

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..150

Wikipedia, Primorial number system.

Index entries for sequences related to primorial base.

EXAMPLE

9 is a term since 9 in primorial base is 111 (9 = 3! + 2! + 1!) and 9 is divisible by 1*1*1 = 1.

MATHEMATICA

max = 12; bases = Prime@Range[max, 1, -1]; nmax = Times @@ bases - 1; q[n_] := FreeQ[(d = IntegerDigits[n, MixedRadix[bases]]), 0] && Divisible[n, Times @@ d]; Select[Range[1, 10^5, 2], q]

CROSSREFS

A143293 is a subsequence.

Subsequence of A328574.

Cf. A007602, A049345, A235168, A286590, A333426.

Sequence in context: A048780 A009864 A128127 * A014857 A177817 A292392

Adjacent sequences: A341430 A341431 A341432 * A341434 A341435 A341436

KEYWORD

nonn,base

AUTHOR

Amiram Eldar, Feb 11 2021

STATUS

approved

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Last modified January 27 02:41 EST 2023. Contains 359836 sequences. (Running on oeis4.)