A086655 (binomial(2*p,p)-2)/(2*p) where p runs through the primes.

1, 3, 25, 245, 32065, 400023, 68635477, 930138521, 178987624513, 518401146543811, 7506908923471953, 23596358977508462295, 5180299766448679532059, 77180849825857621779893, 17294692982395428197325697, 59174764703889164618206676203, 206412709386903552066428869508701

Offset: 1

Author

Benoit Cloitre, Sep 11 2003

Keywords

• nonn

Links

• Amiram Eldar, Table of n, a(n) for n = 1..263

Crossrefs

Cf. A000984, A022553.

Programs

Mathematica

Table[(Binomial[2*p, p] - 2)/(2*p), {p, Prime[Range[18]]}] (* Amiram Eldar, Apr 21 2025 *)

Formula

a(n) = A022553(prime(n)).

Extensions

Typo in definition corrected by Vladimir Shevelev, Sep 05 2010