A131426 a(n) = 2*prime(n) - 3.

1, 3, 7, 11, 19, 23, 31, 35, 43, 55, 59, 71, 79, 83, 91, 103, 115, 119, 131, 139, 143, 155, 163, 175, 191, 199, 203, 211, 215, 223, 251, 259, 271, 275, 295, 299, 311, 323, 331, 343, 355, 359, 379, 383, 391, 395, 419, 443, 451, 455, 463, 475, 479, 499, 511, 523, 535, 539, 551, 559, 563, 583, 611

Offset: 1

Author

Gary W. Adamson, Jul 10 2007

Keywords

• nonn
• easy

Comments

Right border of triangle A131424.

Examples

			a(4) = 11 = 2*p(4) - 3 = 2*7 - 3.
		

Crossrefs

Cf. A000040, A062709, A131424.

Programs

Magma

[2*NthPrime(n) - 3: n in [1..65]]; // Vincenzo Librandi, Mar 30 2015

Maple

A131426:=n->2*ithprime(n)-3: seq(A131426(n), n=1..70); # Wesley Ivan Hurt, Mar 30 2015

Mathematica

2#-3&/@Prime[Range[80]] (* Harvey P. Dale, Jul 24 2011 *)

PARI

a(n) = 2*prime(n) - 3 \\ Charles R Greathouse IV, Jul 12 2016

Formula

a(n) = 2*A000040(n) - 3.