A081384 Numbers k such that binomial(prime(k), k) is divisible by k^2.

1, 60, 624, 663, 1309, 1638, 1950, 2145, 2394, 2470, 2508, 3640, 4186, 5016, 5187, 5928, 6138, 6417, 6479, 7395, 7800, 7920, 7956, 8372, 8415, 8580, 8645, 9350, 10340, 10582, 11220, 11466, 11484, 12540, 12825, 12920, 13325, 13680, 13833, 14620, 14911, 15708

Offset: 1

Author

Labos Elemer, Mar 26 2003

Keywords

• nonn

Links

• Amiram Eldar, Table of n, a(n) for n = 1..500

Crossrefs

Cf. A060604.

Programs

Mathematica

Do[s=Binomial[Prime[n], n]; If[IntegerQ[s/n^2], Print[n]], {n, 1, 10000}]
Select[Range[10000],Divisible[Binomial[Prime[#],#],#^2]&] (* Harvey P. Dale, Mar 10 2013 *)

PARI

is(k) = !(binomial(prime(k), k) % k^2); \\ Amiram Eldar, Oct 04 2024

Extensions

More terms from Harvey P. Dale, Mar 10 2013