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

Author

Clark Kimberling, Aug 18 2024

Keywords

• nonn

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.

Crossrefs

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

Programs

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}]

Formula

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