cp's OEIS Frontend

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.

%I A387198 #25 Aug 31 2025 22:33:06
%S A387198 2,5,10,21,28,45,58,81,106,129,166,201,238,285,338,399,440,511,572,
%T A387198 645,718,811,888,985,1064,1173,1268,1383,1484,1611,1730,1869,1988,
%U A387198 2139,2276,2439,2594,2769,2924,3111,3266,3459,3638,3835,4028,4245,4454,4665,4888,5121,5356
%N 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.
%C A387198 Lower bounds are listed in A007504.
%H A387198 David A. Corneth, <a href="/A387198/b387198.txt">Table of n, a(n) for n = 2..500</a>
%H A387198 Carlos Rivera, <a href="https://www.primepuzzles.net/puzzles/puzz_1233.htm">Puzzle 1233. Sum of Primes such that... </a>, The Prime Puzzles & Problems Connection.
%e A387198 a(2) = 5 because 5 = 2 + 3;
%e A387198 a(3) = 10 because 10 = 3 + 7 = 2 + 3 + 5;
%e A387198 a(4) = 21 because 21 = 2 + 19 = 3 + 5 + 13 = 2 + 3 + 5 + 11;
%e A387198 a(5) = 28 because 28 = 5 + 23 = 2 + 7 + 19 = 3 + 5 + 7 + 13 = 2 + 3 + 5 + 7 + 11; etc.
%Y A387198 Cf. A007504, A073619, A090700, A387215.
%K A387198 nonn,hard,new
%O A387198 1,1
%A A387198 _Paolo P. Lava_, Aug 21 2025
%E A387198 a(22) and more terms from _David A. Corneth_, Aug 21 2025
%E A387198 a(1) prepended by _David A. Corneth_, Aug 26 2025