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 A381374 #4 Feb 23 2025 11:21:36
%S A381374 1,1,97,49,769,289,2977,961,8161,2401,18241,5041,35617,9409,63169,
%T A381374 16129,104257,25921,162721,39601,242881,58081,349537,82369,487969,
%U A381374 113569,663937,152881,883681,201601,1153921,261121,1481857,332929,1875169,418609,2342017,519841,2891041
%N A381374 Little Hankel transform of A317614: a(n) = A317614(n+1)^2 - A317614(n)*A317614(n+2).
%H A381374 <a href="/index/Rec#order_10">Index entries for linear recurrences with constant coefficients</a>, signature (0,5,0,-10,0,10,0,-5,0,1).
%F A381374 a(n) = (10 + 6*(-1)^n + 4*n*(n + 2)*(3*(n + 1)^2 + (-1)^n*(2*n^2 + 4*n + 5)))/16.
%F A381374 a(n) = 5*a(n-2) - 10*a(n-4) + 10*a(n-6) - 5*a(n-8) + a(n-10) for n > 10.
%F A381374 G.f.: (1 + x + 92*x^2 + 44*x^3 + 294*x^4 + 54*x^5 + 92*x^6 - 4*x^7 + x^8 + x^9)/(1 - x^2)^5.
%F A381374 E.g.f.: ((4 + 3*x + 123*x^2 + 10*x^3 + 5*x^4)*cosh(x) + (1 + 69*x + 21*x^2 + 50*x^3 + x^4)*sinh(x))/4.
%F A381374 a(2*n) = A239607(n).
%t A381374 LinearRecurrence[{0,5,0,-10,0,10,0,-5,0,1},{1,97,49,769,289,2977,961,8161,2401,18241},38]
%Y A381374 Cf. A317614.
%Y A381374 Cf. A056221, A056222, A239607, A374668.
%K A381374 nonn,easy
%O A381374 1,3
%A A381374 _Stefano Spezia_, Feb 21 2025