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.

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

Links

Table of n, a(n) for n=1..16.

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

Adjacent sequences: A085628 A085629 A085630 * A085632 A085633 A085634

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