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A277856 Numbers k such that the product of their digits divides both k and R(k), where R(k) is the digits reverse of k. 1
1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 111, 212, 216, 612, 1111, 1113, 1131, 1311, 2112, 3111, 4224, 4416, 6144, 11111, 11133, 11313, 11331, 11711, 13113, 13131, 13311, 21112, 21132, 21312, 23112, 23424, 31113, 31131, 31311, 33111, 42432, 42624, 111111, 211112, 211116 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Subsequence of A007602.

LINKS

David A. Corneth, Table of n, a(n) for n = 1..1228 (first 200 terms from Paola P. Lava, terms < 10^13)

MAPLE

R:=proc(w) local x, y, z; x:=w; y:=0; for z from 1 to ilog10(x)+1 do y:=10*y+(x mod 10); x:=trunc(x/10); od; y; end:

P:=proc(q) local a, n; for n from 1 to q do a:=convert(convert(n, base, 10), `*`);

if a>0 then if R(n) mod a=0 and n mod a=0 then print(n); fi; fi; od; end: P(10^12);

PROG

(PARI) is(n) = { my(d = digits(n), vp = vecprod(d)); if(vp != 0 && n%vp == 0 && fromdigits(Vecrev(d))%vp == 0, return(1) ); 0 } \\ David A. Corneth, Mar 30 2021

CROSSREFS

Cf. A004086, A007602.

Sequence in context: A064704 A083136 A229623 * A117057 A249516 A239090

Adjacent sequences:  A277853 A277854 A277855 * A277857 A277858 A277859

KEYWORD

nonn,base,easy

AUTHOR

Paolo P. Lava, Nov 02 2016

STATUS

approved

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Last modified July 25 14:49 EDT 2021. Contains 346290 sequences. (Running on oeis4.)