A109679 Smallest even number which is the unordered sum of two primes in more ways than any previous even number.

2, 4, 10, 22, 34, 48, 60, 78, 84, 90, 114, 120, 168, 180, 210, 300, 330, 390, 420, 510, 630, 780, 840, 990, 1050, 1140, 1260, 1470, 1650, 1680, 1890, 2100, 2310, 2730, 3150, 3570, 3990, 4200, 4410, 4620, 5250, 5460, 6090, 6510, 6930, 7980, 8190, 9030, 9240

Offset: 1

Author

Gilmar Rodriguez Pierluissi (gilmarlily(AT)yahoo.com), Aug 30 2005

Keywords

• nonn

Comments

Record value of A023036 or A045917.

a(n)== 0 (mod 30) for n > 13.

Links

• Vincenzo Librandi, Table of n, a(n) for n = 1..150
• Eric Weisstein's World of Mathematics, Goldbach Partition
• Index entries for sequences related to Goldbach conjecture

Crossrefs

Essentially the same as A082917. Cf. A082918, A002375, A023036, A045917, A000954.

Programs

Mathematica

f[n_] := Length[ Select[n - Prime@ Range@ PrimePi[n/2], PrimeQ]]; t = {}; mxm = -1; Do[ If[ f[n] > mxm, AppendTo[t, n]; mxm = f[n]], {n, 2, 9000, 2}]; t

Extensions

Edited and extended by Robert G. Wilson v, Sep 08 2005

Changed offset from 0 to 1 by Vincenzo Librandi, Apr 18 2013