%I A076886
%S A076886 1,2,4,8,88,252,2772,27872,2112,4224,8448,44544,48384,2977792,27011072,
%T A076886 405504,4091904,441606144,405909504,886898688,677707776,4285005824,
%U A076886 276486684672,21128282112,633498894336,2701312131072,8691508051968
%N A076886 Smallest palindrome with exactly n prime factors (counted with multiplicity).
%e A076886 a(4)=88 because 88 is the smallest palindromic number with 4 prime factors,
2^3*11 (counted with multiplicity).
%t A076886 f[n_] := Length[ Flatten[ Table[ # [[1]], { # [[2]]}] & /@ FactorInteger[n]]];
a = Table[0, {50}]; Do[b = IntegerDigits[n]; c = FromDigits[ Join[b,
Drop[ Reverse[b], 1]]]; d = FromDigits[ Join[ b, Reverse[b]]]; e
= f[c]; If[ a[[e + 1]] == 0 || a[[e + 1]] > c, a[[e + 1]] = c]; e
= f[d]; If[ a[[e + 1]] == 0 || a[[e + 1]] > d, a[[e + 1]] = d], {n,
1, 18697304}]
%Y A076886 Sequence in context: A018580 A089337 A088114 this_sequence A046385 A068664
A018605
%Y A076886 Adjacent sequences: A076883 A076884 A076885 this_sequence A076887 A076888
A076889
%K A076886 base,nonn
%O A076886 0,2
%A A076886 Shyam Sunder Gupta (guptass(AT)rediffmail.com), Nov 25 2002
%E A076886 Edited and extended by Robert G. Wilson v (rgwv(AT)rgwv.com), Dec 02
2002
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