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A004618 Divisible only by primes congruent to 4 mod 5. 1
1, 19, 29, 59, 79, 89, 109, 139, 149, 179, 199, 229, 239, 269, 349, 359, 361, 379, 389, 409, 419, 439, 449, 479, 499, 509, 551, 569, 599, 619, 659, 709, 719, 739, 769, 809, 829, 839, 841, 859, 919, 929, 1009, 1019 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..1000

MATHEMATICA

ok[1]=True; ok[n_]:=And@@(Mod[#, 5]==4&)/@FactorInteger[n][[All, 1]]; Select[Range[4000], ok] (* Vincenzo Librandi, Aug 20 2012 *)

PROG

(MAGMA) [n: n in [1..1100] | forall{d: d in PrimeDivisors(n) | d mod 5 eq 4}]; // Vincenzo Librandi, Aug 20 2012

CROSSREFS

Sequence in context: A106093 A084666 A242265 * A030433 A242550 A141311

Adjacent sequences:  A004615 A004616 A004617 * A004619 A004620 A004621

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane.

STATUS

approved

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Last modified July 27 04:25 EDT 2017. Contains 289841 sequences.