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A091180 Primes arising in A088878. 30
7, 13, 19, 31, 37, 67, 109, 127, 139, 157, 181, 199, 211, 307, 337, 379, 409, 487, 499, 541, 571, 577, 631, 751, 769, 787, 811, 829, 877, 919, 937, 991, 1009, 1039, 1117, 1201, 1291, 1297, 1327, 1381, 1399, 1459, 1471, 1567, 1621, 1669, 1759, 1777, 1801 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Mother primes of order 1. - Artur Jasinski, Dec 12 2007

LINKS

K. D. Bajpai, Table of n, a(n) for n = 1..10000

FORMULA

a(n) = 3*A088878(n)-2.

EXAMPLE

From K. D. Bajpai, Jun 20 2015: (Start)

a(4) = 31: 3*11 - 2 = 31; A088878(4) = 11.

a(6) = 67: 3*23 - 2 = 67; A088878(6) = 23.

(End)

MAPLE

A091180:= n-> (3*ithprime(n)-2): select(isprime, [seq((A091180(n), n=1..100))]);  # K. D. Bajpai, Jun 20 2015

MATHEMATICA

n = 1; a = {}; Do[If[PrimeQ[(Prime[k] + 2n)/(2n + 1)], AppendTo[a, Prime[k]]], {k, 1, 500}]; a (* Artur Jasinski, Dec 12 2007 *)

Select[Table[3*Prime[n] - 2, {n, 1000}], PrimeQ] (* K. D. Bajpai, Jun 20 2015 *)

PROG

(PARI) forprime(p =  1, 1000, k =( 3*p -2); if ( isprime(k), print1(k, ", "))); \\  K. D. Bajpai, Jun 20 2015

(MAGMA) [ k: p in PrimesUpTo(1000) | IsPrime(k)  where k is (3*p-2) ]; // K. D. Bajpai, Jun 20 2015

CROSSREFS

Cf. A088878, A091179, A091181.

Cf. A136020.

Sequence in context: A081765 A257002 A216567 * A272381 A242190 A053458

Adjacent sequences:  A091177 A091178 A091179 * A091181 A091182 A091183

KEYWORD

easy,nonn

AUTHOR

Ray Chandler, Dec 27 2003

STATUS

approved

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Last modified November 18 17:33 EST 2019. Contains 329287 sequences. (Running on oeis4.)