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A176255 Numbers of the form 4k-1 with least prime divisor of the form 4m+1. 8
35, 55, 95, 115, 155, 175, 215, 235, 247, 275, 295, 299, 323, 335, 355, 391, 395, 403, 415, 455, 475, 515, 527, 535, 559, 575, 595, 611, 635, 655, 695, 715, 731, 755, 767, 775, 799, 815, 835, 871, 875, 895, 899, 923, 935, 955, 995, 1003, 1015, 1027, 1055 (list; graph; refs; listen; history; text; internal format)
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

Cf. A002148, A002145, A016813, A004767.

Sequence in context: A267999 A319386 A157352 * A090877 A048033 A254366

Adjacent sequences:  A176252 A176253 A176254 * A176256 A176257 A176258

KEYWORD

nonn

AUTHOR

Vladimir Shevelev, Apr 13 2010

EXTENSIONS

Terms > 559 from R. J. Mathar, Oct 30 2010

STATUS

approved

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Last modified March 28 20:01 EDT 2020. Contains 333103 sequences. (Running on oeis4.)