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A259978 Terms in A053177 that are relatively prime to 3. 2
35, 95, 119, 143, 203, 215, 275, 299, 335, 395, 455, 515, 527, 539, 623, 635, 695, 707, 767, 779, 803, 899, 923, 935, 959, 1007, 1043, 1115, 1127, 1139, 1175, 1199, 1235, 1295, 1355, 1403, 1547, 1595, 1643, 1655, 1679, 1715, 1727, 1763, 1775, 1859, 1883, 1895 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Lars Blomberg, Table of n, a(n) for n = 1..4332

R. P. Boas & N. J. A. Sloane, Correspondence, 1974

FORMULA

a(n) = 2*A275770(n) + 1. - Hilko Koning, Jul 23 2018

MATHEMATICA

Select[2 Prime@ Range@ 162 + 1, CompositeQ@ # && GCD[3, #] == 1 &] (* Michael De Vlieger, Jul 13 2015 *)

PROG

(PARI) isok(n) = (n % 2) && !isprime(n) && isprime((n-1)/2) && (gcd(n, 3) == 1); \\ Michel Marcus, Jul 28 2018

CROSSREFS

Cf. A053177.

Sequence in context: A020295 A020164 A146206 * A044222 A044603 A063795

Adjacent sequences:  A259975 A259976 A259977 * A259979 A259980 A259981

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane, Jul 12 2015, following a suggestion from R. P. Boas, May 19 1974

EXTENSIONS

More terms from Lars Blomberg, Jul 13 2015

STATUS

approved

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Last modified July 17 20:45 EDT 2019. Contains 325109 sequences. (Running on oeis4.)