A374860 - OEIS

%I #8 Aug 28 2024 10:56:43

%S 1,2,8,40,280,2520,25200,302400,3931200,58968000,1002456000,

%T 18044208000,360884160000,7939451520000,182607384960000,

%U 4565184624000000,118694800224000000,3323454406272000000,99703632188160000000,3090812597832960000000,101996815728487680000000

%N Obverse convolution (1)**A000201; see Comments.

%C 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.

%C A000201 is assumed to start with a(0) = 0.

%F a(n) = Product_{k=0..n} A026351(k).

%t r = GoldenRatio;

%t s[n_] := 1; t[n_] := Floor[n*r];

%t u[n_] := Product[s[k] + t[n - k], {k, 0, n}]

%t Table[u[n], {n, 0, 20}]

%Y Cf. A000012, A000201, A001622, A374848, A026351.

%K nonn

%O 0,2

%A _Clark Kimberling_, Aug 18 2024