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A267896
a(n) = (Prime(n+1)^2 - Prime(n)^2) / 8.
1
2, 3, 9, 6, 15, 9, 21, 39, 15, 51, 39, 21, 45, 75, 84, 30, 96, 69, 36, 114, 81, 129, 186, 99, 51, 105, 54, 111, 420, 129, 201, 69, 360, 75, 231, 240, 165, 255, 264, 90, 465, 96, 195, 99, 615, 651, 225, 114, 231, 354, 120, 615, 381, 390, 399, 135, 411, 279
OFFSET
2,1
LINKS
FORMULA
a(n) = A024675(n) * A028334(n) / 2.
a(n) = (A000040(n+1)^2 - A000040(n)^2) / 8.
a(n) = A069482(n) / 8.
MAPLE
seq((ithprime(n+1)^2 - ithprime(n)^2)/8, n=2..100); # Robert Israel, Jan 22 2016
MATHEMATICA
Rest[Array[(Prime[# + 1]^2 - Prime[#]^2) / 8 &, 60]] (* Vincenzo Librandi, Jan 23 2016 *)
(#[[2]]-#[[1]])/8&/@Partition[Prime[Range[2, 60]]^2, 2, 1] (* Harvey P. Dale, Aug 01 2022 *)
PROG
(PARI) a(n) = (prime(n+1)^2 - prime(n)^2)/8; \\ Michel Marcus, Jan 22 2016
(Magma) [(NthPrime(n+1)^2-NthPrime(n)^2) div 8: n in [2..60]]; // Vincenzo Librandi, Jan 23 2016
CROSSREFS
KEYWORD
nonn
AUTHOR
STATUS
approved