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

1,29

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

Links

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

Example

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.

Crossrefs

Cf. A045917, A104272, A173634.

Sequence in context: A305802 A186038 A091009 * A174903 A167163 A005890

Adjacent sequences: A204811 A204812 A204813 * A204815 A204816 A204817

Keyword

nonn

Author

Donovan Johnson, Jan 27 2012

Status

approved