A374864 Obverse convolution (1)**A001950; see Comments.

1, 3, 18, 144, 1584, 22176, 354816, 6741504, 141571584, 3397718016, 91738386432, 2660413206528, 85133222608896, 2979662791311360, 110247523278520320, 4409900931140812800, 185215839107914137600, 8334712759856136192000, 400066212473094537216000

Offset

0,2

Comments

See A374848 for the definition of obverse convolution and a guide to related sequences. a(n+1)/a(n) is an integer for n>=0, so (a(n)) is a divisibility sequence.

Links

Table of n, a(n) for n=0..18.

Formula

a(n) = Product_{k=0..n} A026352(k).

Mathematica

r = GoldenRatio;
s[n_] := 1; t[n_] := Floor[n*r^2];
u[n_] := Product[s[k] + t[n - k], {k, 0, n}]
Table[u[n], {n, 0, 20}]

Crossrefs

Cf. A000012, A000201, A001622, A026352, A374848.

Sequence in context: A224992 A289428 A123308 * A177383 A074525 A118331

Adjacent sequences: A374861 A374862 A374863 * A374865 A374866 A374867

Keyword

nonn

Author

Clark Kimberling, Aug 18 2024

Status

approved