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 A373622 #13 Jun 12 2024 13:39:09
%S A373622 0,1,6,40,294,2310,19008,161733,1411410,12563408,113624940,1041158846,
%T A373622 9645100416,90182859700,849966450840,8066498833800,77019930780030,
%U A373622 739349587508730,7131313919822400,69079082238199110,671733716498945100,6554862704411317920,64166669054324268120,629964451984076275950
%N A373622 a(n) = A000032(n)*A000045(n)*A000108(n).
%H A373622 Vladimir V. Kruchinin and Maria Y. Perminova, <a href="https://arxiv.org/abs/2406.02937">Identities and Generating Functions of Products of Generalized Fibonacci numbers, Catalan and Harmonic Numbers</a>, arXiv:2406.02937 [math.CO], 2024.
%F A373622 G.f.: (sqrt((-2*sqrt(16*x^2 - 12*x + 1) - 42*x + 7)/5 + 6*x) - 1)/(2*x).
%F A373622 D-finite with recurrence n*(n+1)*a(n) -6*n*(2*n-1)*a(n-1) +4*(2*n-1)*(2*n-3)*a(n-2)=0. - _R. J. Mathar_, Jun 12 2024
%p A373622 gf := (sqrt(-10*sqrt(16*x^2 - 12*x + 1) - 60*x + 35) - 5) / (10*x):
%p A373622 ser := series(gf, x, 32): seq(coeff(ser, x, n), n = 0..22);
%p A373622 # _Peter Luschny_, Jun 11 2024
%t A373622 CoefficientList[Series[(Sqrt[(-2*Sqrt[16*x^2-12*x+1]-42*x+7)/5+6*x]-1)/(2*x),{x,0,23}],x] (* _Stefano Spezia_, Jun 11 2024 *)
%Y A373622 Cf. A000032, A000045, A000108, A119694.
%K A373622 nonn
%O A373622 0,3
%A A373622 _Vladimir Kruchinin_, Jun 11 2024