A387198 Smallest integer that can be expressed as the sum of k different primes, for all k’s between 2 and n, with n >= 2.
2, 5, 10, 21, 28, 45, 58, 81, 106, 129, 166, 201, 238, 285, 338, 399, 440, 511, 572, 645, 718, 811, 888, 985, 1064, 1173, 1268, 1383, 1484, 1611, 1730, 1869, 1988, 2139, 2276, 2439, 2594, 2769, 2924, 3111, 3266, 3459, 3638, 3835, 4028, 4245, 4454, 4665, 4888, 5121, 5356
Offset: 1
Examples
a(2) = 5 because 5 = 2 + 3; a(3) = 10 because 10 = 3 + 7 = 2 + 3 + 5; a(4) = 21 because 21 = 2 + 19 = 3 + 5 + 13 = 2 + 3 + 5 + 11; a(5) = 28 because 28 = 5 + 23 = 2 + 7 + 19 = 3 + 5 + 7 + 13 = 2 + 3 + 5 + 7 + 11; etc.
Links
- David A. Corneth, Table of n, a(n) for n = 2..500
- Carlos Rivera, Puzzle 1233. Sum of Primes such that... , The Prime Puzzles & Problems Connection.
Extensions
a(22) and more terms from David A. Corneth, Aug 21 2025
a(1) prepended by David A. Corneth, Aug 26 2025
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