A261152 a(n) = 161004359399459161 + (n-1)*10644900609172830.

161004359399459161, 171649260008631991, 182294160617804821, 192939061226977651, 203583961836150481, 214228862445323311, 224873763054496141, 235518663663668971, 246163564272841801, 256808464882014631, 267453365491187461, 278098266100360291, 288743166709533121

Offset: 1

Author

Marco Ripà, Aug 10 2015

Keywords

• nonn
• easy

Comments

The terms n = 1..26 are prime. This is the longest and largest sequence of primes in arithmetic progression, a(26)=427126874628779911, known as of August 10, 2015.

Examples

			a(26) = 161004359399459161 + 25*10644900609172830 = 427126874628779911 is prime.
		

Links

• Jens Kruse Andersen, All known AP24 to AP26.
• Wikipedia, Largest known primes in AP.
• Index entries for linear recurrences with constant coefficients, signature (2,-1).

Crossrefs

Cf. A002110, A204189, A260751.

Programs

Magma

[161004359399459161+(n-1)*10644900609172830: n in [1..20]]; // Bruno Berselli, Aug 23 2015

Mathematica

Table[161004359399459161 + (n - 1) 10644900609172830, {n, 1, 20}] (* Bruno Berselli, Aug 23 2015 *)

Formula

a(n) = 161004359399459161 + (n-1)*47715109*A002110(9).

G.f.: x*(161004359399459161 - 150359458790286331*x)/(1 - x)^2. [Bruno Berselli, Aug 23 2015]