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A165993
a(n) = sum_{j=1..prime(n)-1} floor (j^2/prime(n)).
3
0, 1, 4, 11, 31, 44, 80, 103, 157, 252, 293, 420, 520, 575, 695, 884, 1105, 1180, 1431, 1617, 1704, 2007, 2217, 2552, 3040, 3300, 3439, 3713, 3852, 4144, 5255, 5595, 6120, 6305, 7252, 7457, 8060, 8695, 9141, 9804, 10507, 10740, 11983, 12224, 12740
OFFSET
1,3
FORMULA
a(n) = A166375(prime(n)-1). - Charles R Greathouse IV, Jun 28 2013
MATHEMATICA
Table[Sum[Floor[j^2/n], {j, n-1}], {n, Prime[Range[50]]}] (* Harvey P. Dale, Aug 10 2014 *)
PROG
(PARI) a(n) = sum(j=1, prime(n)-1, floor (j^2/prime(n))) \\ Michel Marcus, Jun 20 2013
(PARI) a(n)=my(p=prime(n)); sum(j=1, p-1, j^2\p) \\ Charles R Greathouse IV, Jun 20 2013
CROSSREFS
KEYWORD
nonn
AUTHOR
EXTENSIONS
Definition rephrased by R. J. Mathar, Oct 09 2009
STATUS
approved