A100690 a(n) = p * 5^p - 1 where p=prime(n).

49, 374, 15624, 546874, 537109374, 15869140624, 12969970703124, 362396240234374, 274181365966796874, 5401670932769775390624, 144354999065399169921874, 2692104317247867584228515624

Offset: 1

Author

Parthasarathy Nambi, Dec 07 2004

Keywords

• nonn

Examples

			a(1) = 2*5^2 - 1 = 49.
		

Links

• Harvey P. Dale, Table of n, a(n) for n = 1..224

Programs

Magma

[NthPrime(n) * 5^(NthPrime(n)) - 1: n in [1..20]]; // Vincenzo Librandi, Aug 27 2015

Mathematica

Do[Print[Prime[n]*5^(Prime[n]) - 1], {n, 1, 20}] (* Stefan Steinerberger, Feb 15 2006 *)
#*5^#-1&/@Prime[Range[20]] (* Harvey P. Dale, Jun 12 2016 *)

PARI

main(m)=forprime(p=2,m,print1(p * 5^p - 1,", ")) \\ Anders Hellström, Aug 27 2015

Formula

a(n) = A064751(prime(n)) = A064751(A000040(n)). - Michel Marcus, Aug 27 2015

Extensions

More terms from Stefan Steinerberger, Feb 15 2006