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%I #15 Mar 09 2018 20:12:01
%S 1,2,3,4,5,6,7,8,9,11,13,15,17,22,26,31,33,37,39,44,51,55,58,62,66,71,
%T 73,77,79,85,88,93,97,99,101,107,111,113,115,117,121,122,123,129,131,
%U 141,143,149,151,155,157,158,159,161,165,167,169,171,177,178,179,181
%N Numbers n such that n and its digit reversal have the same prime signature.
%H Alois P. Heinz, <a href="/A085869/b085869.txt">Table of n, a(n) for n = 1..20000</a>
%e 15 is a member 15 = 3*5 and 51 = 3*17 both have the prime signature p*q, p and q are primes.
%p s:= n-> sort(map(i-> i[2], ifactors(n)[2])):
%p a:= proc(n) option remember; local k; for k from 1+a(n-1) while
%p s(k)<>s((p-> parse(cat(seq(p[-i], i=1..length(p)))))(""||k)) do od; k
%p end: a(0):=0:
%p seq(a(n), n=1..80); # _Alois P. Heinz_, Mar 09 2018
%Y Cf. A062895.
%K base,easy,nonn
%O 1,2
%A _Amarnath Murthy_ and Meenakshi Srikanth (menakan_s(AT)yahoo.com), Jul 06 2003
%E Corrected and extended by _Ray Chandler_, Aug 08 2003
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