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%I #6 Mar 30 2012 18:38:59
%S 2,929,39293,3392933,733929337
%N Second palindromic prime pyramids with a(1)=2 such that (number of digits in a(n+1)) = (number of digits in a(n)) + 2.
%C There are only 2 palindromic prime pyramids beginning with 2 (each one is finite with 5 elements).
%D G. L. Honaker Jr. and C. Caldwell, Palindromic prime pyramids, J. Recreational Mathematics, vol. 30.3, pp. 169-176, 1999-2000.
%D J.-P. Delahaye, "Pour la science", (French edition of Scientific American), Juin 2002, p. 99.
%Y Cf. A070922.
%K easy,fini,full,nonn,base
%O 1,1
%A _Benoit Cloitre_, May 24 2002