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A250603
Numbers n whose reversal is a multiple of the reversal of n+1.
1
9, 99, 979, 999, 3199, 3399, 5439, 6399, 6529, 6799, 6999, 8709, 9999, 27099, 40999, 51099, 51199, 52219, 52999, 57499, 98899, 99999, 219699, 521109, 526549, 549399, 570099, 570999, 573499, 578199, 659299, 879099, 999999, 4285099, 4581999, 5218719, 5274199
OFFSET
1,1
EXAMPLE
Rev(9) / Rev(10) = 9 / 1 = 9.
Rev(99) / Rev (100) = 99 / 1 = 99.
Rev(979) / Rev (980) = 979 / 89 = 11.
Rev(999) / Rev (1000) = 999 / 1 = 999. Etc.
MAPLE
with(numtheory): T:=proc(w) local x, y, z; x:=0; y:=w;
for z from 1 to ilog10(w)+1 do x:=10*x+(y mod 10); y:=trunc(y/10); od; x; end;
P:=proc(q) local n; for n from 1 to q do if type(T(n)/T(n+1), integer)
then print(n); fi; od; end: P(10^12);
PROG
(PARI) rev(n)=s=""; for(i=1, #(d=digits(n)), s=concat(d[i], s)); eval(s)
for(n=2, 10^5, if(!(rev(n-1)%rev(n)), print1(n-1, ", "))) \\ Derek Orr, Nov 26 2014
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Paolo P. Lava, Nov 26 2014
STATUS
approved