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A113840 Palindromes that are sandwiched between a prime and a powerful(1) number, in any order. 0
2, 3, 8, 242, 676, 42024, 625946649526, 678176310013671876 (list; graph; refs; listen; history; text; internal format)
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

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Last modified October 18 23:39 EDT 2019. Contains 328211 sequences. (Running on oeis4.)