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Numbers n, not ending in 0, such that n times its digital reverse gives a number made of nontrivial runs of identical digits.
0

%I #5 Nov 21 2013 12:48:48

%S 88,385,583,1426,5929,6241,9295,284213,312482,1001099,9901001,

%T 15046244,44264051,101127144,176452305,220741304

%N Numbers n, not ending in 0, such that n times its digital reverse gives a number made of nontrivial runs of identical digits.

%C A run of length 1 is trivial.

%C Neither n nor (n times its digital reverse) may end in zero. [From Harvey P. Dale, Jan 04 2012]

%e 15046244 * 44364051 = 666007711774444.

%t okQ[n_]:=Module[{idn=IntegerDigits[n],revnt},revnt=n FromDigits[Reverse[ idn]]; Last[idn]!=0&&Last[IntegerDigits[revnt]]!=0&&Min[Length/@Split[ IntegerDigits[revnt]]]>1]; Select[Range[225000000],okQ] (* _Harvey P. Dale_, Jan 04 2012 *)

%Y Cf. A001694, A033023.

%K nonn,base

%O 1,1

%A _Giovanni Resta_, Feb 13 2006