OFFSET
1,1
LINKS
Harvey P. Dale, Table of n, a(n) for n = 1..1000
FORMULA
MAPLE
A000567 := proc(n) n*(3*n-2) ; end: isA014612 := proc(n) RETURN( numtheory[bigomega](n) = 3) ; end: for n from 1 to 300 do q := A000567(n) ; if isA014612(q) then printf("%d, ", q) ; fi; od: # R. J. Mathar, Jan 27 2009
MATHEMATICA
Select[Table[n(3n-2), {n, 200}], PrimeOmega[#]==3&] (* Harvey P. Dale, May 31 2016 *)
PROG
(PARI) issemi(n)=bigomega(n)==2
list(lim)=my(v=List(), t, n=1); while((t=n*(3*n-2))<=lim, if((isprime(n) && issemi(3*n-2)) || (isprime(3*n-2) && issemi(n)), listput(v, t)); n++); Vec(v) \\ Charles R Greathouse IV, Feb 05 2017
CROSSREFS
KEYWORD
nonn
AUTHOR
Giovanni Teofilatto, Jun 06 2007
EXTENSIONS
Corrected and extended by R. J. Mathar, Jan 27 2009
STATUS
approved