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%I #29 Dec 02 2014 20:59:14
%S 252,92529,189252981,1218925298121,212189252981212,12121892529812121,
%T 8121218925298121218,781212189252981212187,1678121218925298121218761,
%U 216781212189252981212187612,22167812121892529812121876122,2221678121218925298121218761222
%N a(1)=252; for n>=1, a(n+1) is the smallest palindromic 5-almost prime with a(n) as a central substring.
%C The 5-almost primes are the numbers that are the product of exactly five (not necessarily distinct).
%e a(1) = 252 = 2*2*3*3*7;
%e a(2) = 92529 = 3*3*3*23*149.
%t d[n_]:= IntegerDigits[n]; t = {x = 252}; Do[i = 1; While[!PrimeOmega[y = FromDigits[Flatten[{z = d[i], d[x], Reverse[z]}]]]==5, i++]; AppendTo[t, x = y], {n, 13}]; t
%Y Cf. A014614, A247483, A247484, A248047.
%K nonn,base
%O 1,1
%A _Michel Lagneau_, Dec 01 2014
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