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A277258 Numbers such that n+R(n) | n*R(n), where R(n) is the digits reverse of n. 1
2, 4, 6, 8, 22, 44, 66, 88, 110, 132, 198, 202, 212, 220, 222, 231, 232, 242, 252, 262, 264, 272, 282, 292, 297, 330, 396, 404, 414, 424, 434, 440, 444, 454, 462, 464, 474, 484, 494, 495, 550, 594, 606, 616, 626, 636, 646, 656, 660, 666, 676, 686, 693, 696, 770 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

This sequence contains all positive terms of A029951. So the sequence is infinite. - Altug Alkan, Oct 07 2016

LINKS

Paolo P. Lava, Table of n, a(n) for n = 1..1000

EXAMPLE

R(132) = 231, (132 * 231) / (132 + 231) = 30492 / 363 = 84.

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 n; for n from 1 to q do if type(n*R(n)/(n+R(n)), integer) then print(n); fi; od; end: P(10^4);

MATHEMATICA

Select[Range@ 770, Function[r, Mod[# r, # + r] == 0]@ FromDigits@ Reverse@ IntegerDigits@ # &] (* Michael De Vlieger, Oct 14 2016 *)

PROG

(PARI) R(n) = eval(concat(Vecrev(Str(n))));

isok(n) = n*R(n) % (n+R(n)) == 0; \\ Michel Marcus, Oct 15 2016

CROSSREFS

Cf. A004086, A029951, A056964, A061205, A131058.

Sequence in context: A321600 A081939 A082615 * A029951 A062287 A189153

Adjacent sequences:  A277255 A277256 A277257 * A277259 A277260 A277261

KEYWORD

nonn,easy,base

AUTHOR

Paolo P. Lava, Oct 07 2016

STATUS

approved

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Last modified May 21 00:41 EDT 2019. Contains 323427 sequences. (Running on oeis4.)