A095840 Number of ways to write the n-th prime power as sum of two prime powers.

0, 1, 1, 2, 2, 2, 3, 3, 3, 3, 4, 3, 3, 2, 3, 4, 3, 3, 7, 2, 3, 3, 2, 3, 2, 2, 3, 7, 2, 2, 3, 2, 4, 4, 3, 2, 2, 2, 2, 2, 4, 2, 3, 1, 11, 3, 3, 4, 0, 2, 3, 1, 3, 3, 3, 1, 4, 1, 1, 2, 4, 2, 1, 3, 3, 2, 1, 3, 5, 1, 12, 3, 2, 1, 3, 2, 2, 3, 2, 4, 2, 1, 2, 2, 0, 1, 1, 3, 2, 4, 2, 3, 2, 0, 2, 3, 1, 2, 2, 2, 1, 3

Offset: 1

Author

Reinhard Zumkeller, Jun 10 2004

Keywords

• nonn

Comments

a(n) = A071330(A000961(n)).

See A095842 and A095841 for prime powers having no more than one partition into two prime powers.

Examples

			A000961(8) = 3^2 = 9 = 1+8 = 2+7 = 4+5, therefore a(8)=3.
		

Links

• Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

Programs

Haskell

a095840 = a071330 . a000961  -- Reinhard Zumkeller, Jan 11 2013