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A004620 Divisible only by primes congruent to 2 mod 7. 1
1, 2, 4, 8, 16, 23, 32, 37, 46, 64, 74, 79, 92, 107, 128, 148, 149, 158, 163, 184, 191, 214, 233, 256, 296, 298, 316, 317, 326, 331, 359, 368, 373, 382, 401, 428, 443, 457, 466, 499, 512, 529, 541, 569, 592, 596 (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[#, 7]==2&)/@FactorInteger[n][[All, 1]]; Select[Range[6000], ok] (* Vincenzo Librandi, Aug 20 2012 *)

PROG

(MAGMA) [n: n in [1..1000] | forall{d: d in PrimeDivisors(n) | d mod 7 eq 2}]; // Vincenzo Librandi, Aug 20 2012

CROSSREFS

Sequence in context: A004207 A219675 A062729 * A018618 A294364 A108566

Adjacent sequences:  A004617 A004618 A004619 * A004621 A004622 A004623

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane.

EXTENSIONS

Offset changed from 0 to 1 by Vincenzo Librandi, Aug 20 2012

STATUS

approved

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Last modified November 15 21:37 EST 2019. Contains 329168 sequences. (Running on oeis4.)