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%I #10 Aug 11 2022 03:20:08
%S 1,2,10,35,210,1287,5005,31824,125970,817190,5311735,21474180,
%T 141120525,927983760,3796297200,25140840660,103077446706,686353797976,
%U 4568648125690,18851684897584,125994627894135,520341450264090
%N a(n) = binomial(floor(n*(sqrt(5)+3)/2), n) for n>=0.
%F a(n) = binomial(A001950(n), A000201(n)), where A001950(n) = floor(n*phi^2) and A000201(n) = floor(n*phi) are the upper and lower Wythoff sequences, respectively, with phi = (sqrt(5)+1)/2.
%o (PARI) a(n)=binomial(floor(n*(sqrt(5)+3)/2),n)
%o (PARI) {a(n)=local(phi=(sqrt(5)+1)/2);binomial(floor(n*phi^2),floor(n*phi))}
%o (Python)
%o from math import isqrt, comb
%o def A135963(n): return comb(n+(n+isqrt(5*n**2)>>1),n) # _Chai Wah Wu_, Aug 10 2022
%Y Cf. A135962; A001950, A000201.
%K nonn
%O 0,2
%A _Paul D. Hanna_, Dec 11 2007