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%I #8 Dec 17 2012 14:39:01
%S 2,3,8,242,676,42024,625946649526,678176310013671876
%N Palindromes that are sandwiched between a prime and a powerful(1) number, in any order.
%C Here we are considering powerful numbers (first definition) A001694. Note that, by definition, 1 is powerful.
%C a(9) > 10^18. [From _Donovan Johnson_, Oct 01 2009]
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/PowerfulNumber.html">Powerful Number.</a>
%e 42023 prime, 42024 palindrome, 42025=5^2*41^2 powerful(1).
%e 625946649525=3^2*5^2*29^2*149^3 powerful(1), 625946649526 palindrome, 625946649527 prime.
%Y Cf. A001694, A002113.
%K base,hard,nonn
%O 1,1
%A _Giovanni Resta_, Jan 24 2006
%E a(8) from _Donovan Johnson_, Oct 01 2009
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