This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A146977 #10 Sep 08 2022 08:45:38
%S A146977 8,28,350,4706,956384,14061140,3143981870,47564380970,11061198475550,
%T A146977 40328534467494098,624021469287616610,2338958497948612884092,
%U A146977 568740383597968804344752,8885203954833615367662872,2175457720411301277807088352,8390179243143767727343229863076
%N A146977 a(n) = Sum_{k=1..prime(n)} binomial(2k,k).
%H A146977 G. C. Greubel, <a href="/A146977/b146977.txt">Table of n, a(n) for n = 1..250</a>
%p A146977 seq( add(binomial(2*k,k), k=1..ithprime(n)), n=1..15); # _G. C. Greubel_, Jan 09 2020
%t A146977 Table[Sum[Binomial[2k,k],{k,Prime[n]}],{n,15}] (* _Harvey P. Dale_, Dec 31 2012 *)
%o A146977 (PARI) vector(15, n, sum(k=1,prime(n), binomial(2*k,k)) ) \\ _G. C. Greubel_, Jan 09 2020
%o A146977 (Magma) [ &+[Binomial(2*k,k): k in [1..NthPrime(n)]]: n in [1..15]]; // _G. C. Greubel_, Jan 09 2020
%o A146977 (Sage) [sum(binomial(2*k,k) for k in (1..nth_prime(n))) for n in (1..15)] # _G. C. Greubel_, Jan 09 2020
%Y A146977 A subsequence of A066796.
%K A146977 nonn
%O A146977 1,1
%A A146977 _N. J. A. Sloane_, Apr 25 2009