A204814 Number of decompositions of 2n into an unordered sum of two Ramanujan primes.

0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 3, 0, 0, 1, 0, 0, 2, 0, 0, 2, 1, 0, 2, 1, 0, 3, 0, 0, 1, 1, 0, 2, 0, 0, 1, 2, 0, 2, 2, 0, 4, 0, 0, 1, 2, 0, 2, 0, 1, 1, 3, 0, 2, 2, 0, 2, 0, 0, 1, 2, 0, 2, 1, 1, 2, 4, 0, 1, 2

Offset: 1

Author

Donovan Johnson, Jan 27 2012

Keywords

• nonn

Comments

Suggested by John W. Nicholson.

There are 95 zeros in the first 10000 terms. Are there more? Related to Goldbach's conjecture. - T. D. Noe, Jan 27 2012

There are no other zeros in the first 10^8 terms. a(n) > 0 for n from 1313 to 10^8. - Donovan Johnson, Jan 27 2012

Examples

			a(29) = 3. 2*29 = 58 = 11+47 = 17+41 = 29+29 (11, 17, 29, 41 and 47 are all Ramanujan primes). 58 is the unordered sum of two Ramanujan primes in three ways.
		

Links

• Donovan Johnson, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A045917, A104272, A173634.