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A337134
a(n) = Sum_{k=1..n} floor(sqrt(2k-1)).
1
1, 2, 4, 6, 9, 12, 15, 18, 22, 26, 30, 34, 39, 44, 49, 54, 59, 64, 70, 76, 82, 88, 94, 100, 107, 114, 121, 128, 135, 142, 149, 156, 164, 172, 180, 188, 196, 204, 212, 220, 229, 238, 247, 256, 265, 274, 283, 292, 301, 310, 320, 330, 340, 350, 360, 370, 380, 390, 400, 410, 421, 432
OFFSET
1,2
COMMENTS
Partial sums of A103128.
MATHEMATICA
Table[Sum[Floor[Sqrt[2 i - 1]], {i, n}], {n, 100}]
PROG
(PARI) a(n) = sum(k=1, n, sqrtint(2*k-1)); \\ Michel Marcus, Aug 18 2020
CROSSREFS
Cf. A103128.
Sequence in context: A296349 A325544 A118103 * A185601 A157795 A294060
KEYWORD
nonn,easy
AUTHOR
Wesley Ivan Hurt, Aug 18 2020
STATUS
approved