The OEIS is supported by the many generous donors to the OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A352865 a(0) = 1; a(n) = Sum_{k=0..floor((n-1)/2)} (-1)^k * binomial(n-k,k) * a(n-2*k-1). 3
 1, 1, 1, -1, -4, -5, 6, 36, 46, -101, -515, -506, 2554, 9991, 3067, -79915, -227056, 205681, 2841708, 5134140, -18296153, -107927240, -66578269, 1174691649, 4059143386, -4667894370, -69377504739, -126787267800, 669710503012, 3835079736835, 475781902203 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,5 LINKS Table of n, a(n) for n=0..30. FORMULA G.f. A(x) satisfies: A(x) = 1 + x * A(x/(1 + x^2)) / (1 + x^2)^2. MATHEMATICA a[0] = 1; a[n_] := a[n] = Sum[(-1)^k Binomial[n - k, k] a[n - 2 k - 1], {k, 0, Floor[(n - 1)/2]}]; Table[a[n], {n, 0, 30}] nmax = 30; A[_] = 0; Do[A[x_] = 1 + x A[x/(1 + x^2)]/(1 + x^2)^2 + O[x]^(nmax + 1) // Normal, nmax + 1]; CoefficientList[A[x], x] CROSSREFS Cf. A014619, A172385, A352864. Sequence in context: A287648 A081406 A019067 * A095212 A166042 A321772 Adjacent sequences: A352862 A352863 A352864 * A352866 A352867 A352868 KEYWORD sign AUTHOR Ilya Gutkovskiy, Apr 06 2022 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified September 30 05:13 EDT 2023. Contains 365781 sequences. (Running on oeis4.)