cp's OEIS Frontend

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.

A354210 a(n) = floor(sqrt(Fibonacci(n+1)*Fibonacci(n))).

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%I A354210 #13 Jan 05 2025 19:51:42
%S A354210 0,1,1,2,3,6,10,16,26,43,69,113,183,296,479,775,1255,2031,3286,5318,
%T A354210 8605,13923,22528,36452,58981,95433,154414,249847,404261,654109,
%U A354210 1058371,1712480,2770851,4483332,7254184,11737516,18991701,30729217,49720919,80450136,130171055,210621192
%N A354210 a(n) = floor(sqrt(Fibonacci(n+1)*Fibonacci(n))).
%H A354210 P. Ferraro, <a href="https://web.archive.org/web/2024*/https://www.fq.math.ca/Problems/FQElemProbMay2021.pdf">Problem B-1288</a>, Fibonacci Q., 59 (No. 2, May 2021) p. 177.
%F A354210 a(n) = floor(sqrt(A001654(n))).
%t A354210 a[n_] := Floor[Sqrt[Fibonacci[n + 1] * Fibonacci[n]]]; Array[a, 42, 0] (* _Amiram Eldar_, May 19 2022 *)
%o A354210 (PARI) a(n) = sqrtint(fibonacci(n+1)*fibonacci(n));
%o A354210 (Python)
%o A354210 from math import prod
%o A354210 from gmpy2 import isqrt, fib2
%o A354210 def A354210(n): return int(isqrt(prod(fib2(n+1)))) # _Chai Wah Wu_, May 19 2022
%Y A354210 Cf. A000045, A001654, A061287, A199575.
%K A354210 nonn
%O A354210 0,4
%A A354210 _Michel Marcus_, May 19 2022