A121823 (3^p+p)/(p+1) with (p + 1) odd prime > 3.

17, 105, 5369, 40881, 2532161, 20390553, 1364393897, 788854912241, 6641649422409, 4056611764783761, 296528425830656801, 2544627654221217657, 188573151481968108425, 121907205457107043376081, 79832689783834658219010233, 694937020905183664168761201, 461241110188546453162994653785, 35255711337932980300219323747689

Offset: 1

Author

Zak Seidov, Aug 27 2006

Keywords

• nonn

Comments

See comments in A057900.

Examples

			a(1) = (3^4 + 4)/(4+1) = 17, a(2) = (3^6 + 6)/(6+1) = 105.
		

Links

• Robert Israel, Table of n, a(n) for n = 1..315

Crossrefs

Cf. A057900.

Programs

Maple

map(t -> (3^(t-1)+t-1)/t, select(isprime,[seq(i,i=5..100,2)])); # Robert Israel, Nov 13 2017

Extensions

Corrected and edited according to suggestion of Michel Marcus by Zak Seidov, Oct 20 2013

More terms from Robert Israel, Nov 13 2017