OFFSET
1,1
COMMENTS
By definition, all terms are composite numbers.
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..10000
MAPLE
A020639 := proc(n) if n = 1 then 1; else min(op(numtheory[factorset](n))) ; end if; end proc:
isA176255 := proc(n) (n mod 4 = 3) and ( A020639(n) mod 4 = 1) ; end proc:
for n from 3 to 1200 by 4 do if isA176255(n) then printf("%d, ", n); end if; end do:
# R. J. Mathar, Oct 30 2010
MATHEMATICA
Select[4 Range@ 265 - 1, Mod[#, 4] == 1 &[FactorInteger[#][[1, 1]]] &] (* Michael De Vlieger, Feb 07 2016 *)
PROG
(PARI) isok(n) = ((n % 4) == 3) && ((vecmin(factor(n)[, 1]) % 4) == 1); \\ Michel Marcus, Feb 07 2016
(Magma) [n: n in [1..1500] | (n mod 4 eq 3) and (Min(PrimeFactors(n)) mod 4) eq 1]; // Vincenzo Librandi, Feb 07 2016
CROSSREFS
KEYWORD
nonn
AUTHOR
Vladimir Shevelev, Apr 13 2010
EXTENSIONS
Terms > 559 from R. J. Mathar, Oct 30 2010
STATUS
approved