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A165994
a(n) is the number of nonzero values of floor (j^2/prime(n)), over 1 <= j < prime(n).
1
0, 1, 2, 4, 7, 9, 12, 14, 18, 23, 25, 30, 34, 36, 40, 45, 51, 53, 58, 62, 64, 70, 73, 79, 87, 90, 92, 96, 98, 102, 115, 119, 125, 127, 136, 138, 144, 150, 154, 159, 165, 167, 177, 179, 182, 184, 196, 208, 211, 213, 217, 223, 225, 235, 240, 246, 252, 254, 260
OFFSET
1,3
FORMULA
a(n) = floor(A000040(n) - sqrt(A000040(n))). - Jon Maiga, Nov 13 2018
MATHEMATICA
Table[Floor[Prime[n] - Sqrt[Prime[n]]], {n, 60}] (* Vincenzo Librandi, Nov 13 2018 *)
PROG
(Magma) [Floor(NthPrime(n) - Sqrt(NthPrime(n))): n in [1..60]]; // Vincenzo Librandi, Nov 13 2018
CROSSREFS
Cf. A165974.
Sequence in context: A189677 A087733 A065027 * A163293 A188045 A247912
KEYWORD
nonn
AUTHOR
EXTENSIONS
Definition rephrased by R. J. Mathar, Oct 09 2009
STATUS
approved