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A085631
Let b(n)=product of exponents of prime factorization of n. Sequence gives palindromes n such that b(n) is also palindromic and sets a new record.
0
1, 4, 8, 252, 2112, 4224, 8448, 29592, 6547456, 27011072, 291080192, 276444444672, 2789387839872, 6399369639936, 631367020763136, 2306938998396032
OFFSET
1,2
COMMENTS
No more terms < 1.45*10^14. - David Wasserman, Feb 07 2005
a(17) > 10^18. - Donovan Johnson, Mar 26 2010
EXAMPLE
a(9)=6547456 because it is a palindrome and 6547456 = 2^11*23*139 and
11*1*1=11 a palindrome.
CROSSREFS
Cf. A005361.
Sequence in context: A013096 A200729 A116092 * A074073 A090653 A065022
KEYWORD
base,nonn
AUTHOR
Jason Earls and Amarnath Murthy, Jul 10 2003
EXTENSIONS
More terms from David Wasserman, Feb 07 2005
a(15)-a(16) from Donovan Johnson, Mar 26 2010
STATUS
approved