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A347912
a(n) = Sum_{k=1..n} k - floor(sqrt(k)+1/2) * floor(sqrt(k-1)).
0
1, 2, 3, 5, 6, 8, 9, 11, 14, 15, 17, 20, 21, 23, 26, 30, 31, 33, 36, 40, 41, 43, 46, 50, 55, 56, 58, 61, 65, 70, 71, 73, 76, 80, 85, 91, 92, 94, 97, 101, 106, 112, 113, 115, 118, 122, 127, 133, 140, 141, 143, 146, 150, 155, 161, 168, 169, 171, 174, 178, 183, 189, 196, 204
OFFSET
1,2
COMMENTS
Partial sums of A122197.
MATHEMATICA
Table[Sum[k - Floor[Sqrt[k] + 1/2]*Floor[Sqrt[k - 1]], {k, n}], {n, 100}]
CROSSREFS
Cf. A122197.
Sequence in context: A309793 A093689 A097702 * A082583 A274332 A005097
KEYWORD
nonn,easy
AUTHOR
Wesley Ivan Hurt, Sep 18 2021
STATUS
approved