OFFSET
1,2
LINKS
K. D. Bajpai, Table of n, a(n) for n = 1..3689
EXAMPLE
a(2) = 8 = 2^3: 2^3 + 3^3 = 35 = 5*7 which is a semiprime.
a(4) = 125 = 5^3: 5^3 + 6^3 = 341 = 11*31 which is a semiprime.
MAPLE
with(numtheory):KD:= proc() local a, b; a:=n^3+(n+1)^3; b:=bigomega(a); if b=2 then RETURN (n^3); fi; end: seq(KD(), n=1..500);
MATHEMATICA
Transpose[Select[Partition[Range[250]^3, 2, 1], PrimeOmega[Total[#]] == 2&]] [[1]] (* Harvey P. Dale, Dec 15 2015 *)
PROG
(PARI) forprime(p=3, 1e4, if(isprime((p^2+3)/4), print1((p^3 - 3*p^2 + 3*p - 1)/8", "))) \\ Charles R Greathouse IV, Aug 25 2014
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
K. D. Bajpai, Apr 13 2014
STATUS
approved