

A113840


Palindromes that are sandwiched between a prime and a powerful(1) number, in any order.


0




OFFSET

1,1


COMMENTS

Here we are considering powerful numbers (first definition) A001694. Note that, by definition, 1 is powerful.
a(9) > 10^18. [From Donovan Johnson, Oct 01 2009]


LINKS

Table of n, a(n) for n=1..8.
Eric Weisstein's World of Mathematics, Powerful Number.


EXAMPLE

42023 prime, 42024 palindrome, 42025=5^2*41^2 powerful(1).
625946649525=3^2*5^2*29^2*149^3 powerful(1), 625946649526 palindrome, 625946649527 prime.


CROSSREFS

Cf. A001694, A002113.
Sequence in context: A324006 A112237 A132502 * A285088 A075849 A005604
Adjacent sequences: A113837 A113838 A113839 * A113841 A113842 A113843


KEYWORD

base,hard,nonn


AUTHOR

Giovanni Resta, Jan 24 2006


EXTENSIONS

a(8) from Donovan Johnson, Oct 01 2009


STATUS

approved



