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A278440
Numbers n such that A244112(n) | n.
4
22, 777, 4444, 68868, 200000, 303030, 333000, 333333, 555555, 660000, 660660, 666666, 700000, 2332200, 3131313, 4444400, 6060600, 7007000, 7700000, 9009790, 9656955, 9885585, 11517771, 14233221, 14331231, 14333110, 14411040, 15143331, 15233221, 15331231, 15333110
OFFSET
1,1
COMMENTS
A244112(68868) = 3826 and 68868 / 3826 = 18.
LINKS
MAPLE
with(numtheory): P:=proc(q) local a, b, c, d, j, k, n; for n from 1 to q do a:=sort(convert(n, base, 10));
for k from 1 to trunc(nops(a)/2) do c:=a[k]; a[k]:=a[nops(a)-k+1]; a[nops(a)-k+1]:=c; od; k:=1; b:=a[1]; c:=0;
for j from 2 to nops(a) do if a[j]=b then k:=k+1; else d:=10*k+b; c:=c*10^(ilog10(d)+1)+d; k:=1; b:=a[j]; fi; od;
d:=10*k+b; c:=c*10^(ilog10(d)+1)+d; if type(n/c, integer) then print(n); fi; od; end: P(10^99);
MATHEMATICA
Select[Range[10^6], Divisible[#, FromDigits@ Flatten@ Map[IntegerDigits, DeleteCases[#, k_ /; First@ k == 0]] &@ Reverse@ MapIndexed[{#1, (First@ #2 - 1)} &, RotateRight@ DigitCount@ #]] &] (* Michael De Vlieger, Dec 12 2016 *)
CROSSREFS
KEYWORD
nonn,easy,base
AUTHOR
Paolo P. Lava, Nov 25 2016
STATUS
approved