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A253601 Numbers such that the smallest exponent for n and n^k to have common digits is 3. 3
4, 9, 17, 18, 24, 29, 33, 34, 38, 39, 44, 54, 57, 58, 59, 62, 67, 72, 79, 84, 88, 94, 144, 158, 173, 194, 209, 212, 224, 237, 238, 244, 247, 253, 257, 259, 307, 313, 314, 333, 334, 338, 349, 353, 359, 377, 388, 404, 409, 424, 437, 444, 447, 449, 454, 459, 467 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Iain Fox, Table of n, a(n) for n = 1..10000

EXAMPLE

4^2=16 has no digits in common with 4, but 4^3=64 has some, so 4 is in the sequence.

PROG

(PARI) a253600(n) = {sd = Set(vecsort(digits(n))); k=2; while (#setintersect(sd, Set(vecsort(digits(n^k)))) == 0, k++); k; }

isok(n) = a253600(n) == 3;

(PARI) is(n) = my(d(k)=Set(digits(n^k))); !#setintersect(d(1), d(2)) && #setintersect(d(1), d(3)) \\ Iain Fox, Aug 07 2018

CROSSREFS

Cf. A103173, A189056, A253600, A253602.

Sequence in context: A110979 A073173 A313352 * A313353 A341789 A313354

Adjacent sequences:  A253598 A253599 A253600 * A253602 A253603 A253604

KEYWORD

nonn,base

AUTHOR

Michel Marcus, Jan 05 2015

STATUS

approved

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Last modified August 16 21:38 EDT 2022. Contains 356169 sequences. (Running on oeis4.)