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A025117
a(n) = s(1)t(n) + s(2)t(n-1) + ... + s(k)t(n-k+1), where k = [ n/2 ], s = (odd natural numbers), t = (primes).
1
3, 5, 22, 32, 81, 111, 212, 256, 429, 519, 794, 926, 1329, 1537, 2092, 2368, 3109, 3427, 4376, 4818, 6001, 6495, 7938, 8542, 10287, 11075, 13148, 14074, 16491, 17505, 20314, 21444, 24679, 26067, 29768, 31298, 35493, 37249, 41972, 44054, 49343, 51607, 57494
OFFSET
1,1
MATHEMATICA
Table[Sum[(2 k - 1) Prime[n - k + 2], {k, Floor[(n + 1)/2]}], {n, 50}] (* Wesley Ivan Hurt, Jan 18 2022 *)
CROSSREFS
Sequence in context: A025112 A203192 A025098 * A318076 A124423 A209109
KEYWORD
nonn
STATUS
approved