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A113840
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Palindromes that are sandwiched between a prime and a powerful(1) number, in any order.
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0
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OFFSET
| 1,1
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COMMENTS
| Here we are considering powerful numbers (first definition) A001694. Note that, by definition, 1 is powerful.
a(9) > 10^18. [From Donovan Johnson (donovan.johnson(AT)yahoo.com), Oct 01 2009]
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LINKS
| Eric Weisstein's World of Mathematics, Link to a section of The World of Mathematics.
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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.
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CROSSREFS
| Cf. A001694, A002113.
Sequence in context: A079938 A112237 A132502 * A075849 A005604 A114020
Adjacent sequences: A113837 A113838 A113839 * A113841 A113842 A113843
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KEYWORD
| base,hard,nonn
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AUTHOR
| Giovanni Resta (g.resta(AT)iit.cnr.it), Jan 24 2006
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EXTENSIONS
| a(8) from Donovan Johnson (donovan.johnson(AT)yahoo.com), Oct 01 2009
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