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A257226 Numbers that have at least one divisor containing the digit 9 in base 10. 7
9, 18, 19, 27, 29, 36, 38, 39, 45, 49, 54, 57, 58, 59, 63, 69, 72, 76, 78, 79, 81, 87, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 108, 109, 114, 116, 117, 118, 119, 126, 129, 133, 135, 138, 139, 144, 145, 147, 149, 152, 153, 156, 158, 159, 162, 169, 171, 174 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Numbers k whose concatenation of divisors A037278(k), A176558(k), A243360(k) or A256824(k) contains a digit 9.

A011539 (numbers that contain a 9) is a subsequence.

LINKS

Table of n, a(n) for n=1..59.

FORMULA

a(n) ~ n.

EXAMPLE

18 is in sequence because the list of divisors of 18: (1, 2, 3, 6, 9, 18) contains digit 9.

MATHEMATICA

Select[Range@108, Part[Plus @@ DigitCount@ Divisors@ #, 9] > 0 &] (* after Michael De Vlieger *)

PROG

(MAGMA) [n: n in [1..1000] | [9] subset Setseq(Set(Sort(&cat[Intseq(d): d in Divisors(n)])))]

(PARI) is(n)=fordiv(n, d, if(setsearch(Set(digits(d)), 9), return(1))); 0 \\ after Charles R Greathouse IV

CROSSREFS

Cf. A037278, A176558, A243360, A256824.

Cf. similar sequences with another digit: A209932 (0), A000027 (1), A257219 (2), A257220 (3), A257221 (4), A257222 (5), A257223 (6), A257224 (7), A257225 (8).

Sequence in context: A296711 A297144 A107977 * A092457 A062057 A254066

Adjacent sequences:  A257223 A257224 A257225 * A257227 A257228 A257229

KEYWORD

nonn,base

AUTHOR

Jaroslav Krizek, May 29 2015

STATUS

approved

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Last modified June 14 16:56 EDT 2021. Contains 345037 sequences. (Running on oeis4.)