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A079415
a(n) = floor(prime(n)/n) * ceiling(prime(n)/n) / 2.
1
2, 1, 1, 1, 3, 3, 3, 3, 3, 3, 3, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 15, 10, 10, 10, 15, 15, 15, 15, 15, 15, 15
OFFSET
1,1
LINKS
MATHEMATICA
fc[n_]:=Module[{c=Prime[n]/n}, (Floor[c]Ceiling[c])/2]; Array[fc, 80] (* Harvey P. Dale, May 20 2015 *)
PROG
(PARI) vector(80, n, floor(prime(n)/n)*ceil(prime(n)/n)/2) \\ G. C. Greubel, Jan 19 2019
(Magma) [Floor(NthPrime(n)/n)*Ceiling(NthPrime(n)/n)/2: n in [1..80]]; // G. C. Greubel, Jan 19 2019
(Sage) [floor(nth_prime(n)/n)*ceil(nth_prime(n)/n)/2 for n in (1..80)] # G. C. Greubel, Jan 19 2019
CROSSREFS
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Jan 07 2003
STATUS
approved