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A340288
a(n) = Sum_{k=1..n} floor(floor((n-k)^(1/k))/k).
1
0, 1, 2, 3, 4, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 32, 33, 34, 35, 36, 37, 38, 39, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 70, 71, 72, 73, 74, 75, 76
OFFSET
1,3
MATHEMATICA
Table[Sum[Floor[Floor[(n - k)^(1/k)]/k], {k, n}], {n, 100}]
PROG
(PARI) a(n) = sum(k=1, n, sqrtnint(n-k, k)\k); \\ Michel Marcus, Jan 03 2021
CROSSREFS
Cf. A340289.
Sequence in context: A099260 A231237 A053241 * A132329 A230313 A052413
KEYWORD
nonn
AUTHOR
Wesley Ivan Hurt, Jan 03 2021
STATUS
approved