OFFSET
1,3
LINKS
Michael De Vlieger, Table of n, a(n) for n = 1..10000
FORMULA
Multiplicative with a(p^e) = p^A011765(p+1), e > 0. - R. J. Mathar, Jun 07 2011
MAPLE
A170819 := proc(n) a := 1 ; for p in numtheory[factorset](n) do if p mod 4 = 3 then a := a*p ; end if; end do: a ; end proc:
seq(A170819(n), n=1..20) ; # R. J. Mathar, Jun 07 2011
MATHEMATICA
Array[Times @@ Select[FactorInteger[#][[All, 1]], Mod[#, 4] == 3 &] &, 85] (* Michael De Vlieger, Feb 19 2019 *)
PROG
(PARI) for(n=1, 99, t=select(x->x%4==3, factor(n)[, 1]); print1(prod(i=1, #t, t[i])", "))
CROSSREFS
KEYWORD
nonn,mult
AUTHOR
N. J. A. Sloane, Dec 23 2009
EXTENSIONS
Extended with PARI program by M. F. Hasler, Dec 23 2009
STATUS
approved