A173634 Even numbers that are not the sum of 2 Ramanujan primes (A104272).

2, 6, 8, 10, 12, 14, 16, 18, 20, 24, 26, 30, 32, 36, 38, 42, 44, 48, 50, 54, 56, 60, 62, 66, 68, 72, 74, 80, 86, 90, 92, 98, 102, 104, 110, 116, 120, 122, 128, 132, 140, 146, 150, 152, 158, 170, 176, 182, 188, 200, 206, 212, 230, 232, 236, 242, 260, 266, 272, 284, 290, 314, 320, 344, 350, 372, 386, 398, 424, 428, 452, 484, 512, 542, 556, 564, 572, 626, 632, 644, 686, 692, 764, 962, 986, 1022, 1028, 1070, 1532, 1712, 1742, 1766, 2078, 2582, 2624

Offset

1,1

Comments

No other terms < 2*10^8. Conjectured to be complete.

a(n) = 2*(n of A204814) when a204814(n) = 0. Related to Goldbach's conjecture in that (Conjecture:) even numbers 2626 and greater are the sum of two Ramanujan primes. - John W. Nicholson, Jan 26 2017

Links

Table of n, a(n) for n=1..95.

Eric Weisstein's World of Mathematics, Ramanujan Prime

Wikipedia, Ramanujan prime

Example

68 is a term because no 2 Ramanujan primes sum to 68. 70 is not a term because 11 + 59 = 70. 11 and 59 are both Ramanujan primes.

Crossrefs

Cf. A104272.

Sequence in context: A121744 A336986 A198832 * A005795 A319827 A327905

Adjacent sequences: A173631 A173632 A173633 * A173635 A173636 A173637

Keyword

nonn

Author

Donovan Johnson, Nov 23 2010

Status

approved