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.
%I A381503 #18 Mar 14 2025 21:19:30 %S A381503 1,3,18,90,540,3276,21021,137445,916300,6167700,41812200,284604840, %T A381503 1942428033,13278352815,90862598190,622150990734,4261620339460, %U A381503 29198279495220,200080147593645,1371167039301345,9397260307853496,64406143791454248,441430873666787088,3025546968019741200 %N A381503 Number of rectangles in a Fibonacci(n) X Fibonacci(n+1) grid. %H A381503 Paolo Xausa, <a href="/A381503/b381503.txt">Table of n, a(n) for n = 1..1000</a> %F A381503 a(n) = A096948(Fibonacci(n),Fibonacci(n+1)). %F A381503 a(n) = A033192(n) * A033192(n+1). %t A381503 Times @@@ Partition[PolygonalNumber[Fibonacci[Range[25]]], 2, 1] (* _Paolo Xausa_, Mar 13 2025 *) %o A381503 (Python) %o A381503 from sympy import fibonacci %o A381503 A096948 = lambda n,m: (m * (m + 1) * n * (n + 1)) >> 2 %o A381503 a = lambda n: A096948(fibonacci(n),fibonacci(n+1)) %o A381503 print([a(n) for n in range(1, 25)]) %Y A381503 Cf. A000045, A033192, A096948, A377704. %K A381503 nonn,easy %O A381503 1,2 %A A381503 _Darío Clavijo_, Feb 25 2025