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 A076621 #15 Jan 11 2025 05:20:45 %S A076621 9,16,36,81,144,225,324,441,676,900,1156,1521,1764,2025,2500,3136, %T A076621 3600,4096,4761,5184,5776,6561,7396,8649,9801,10404,11025,11664,12321, %U A076621 14400,16641,17956,19044,20736,22500,23716,25600,27225,28900,30976,32400,34596,36864 %N A076621 Least square greater than the product of two successive primes. %F A076621 a(n) = A048761(A006094(n)). %F A076621 a(n) = prime(n)*prime(n+1)+((prime(n)-prime(n+1))/2)^2 = A006094(n) + A074927(n) for n > 1. %F A076621 a(n) = ((prime(n)+prime(n+1))/2)^2 for n > 1. %t A076621 Ceiling[Sqrt[Times@@#]]^2&/@Partition[Prime[Range[50]],2,1] (* _Harvey P. Dale_, Aug 26 2013 *) %o A076621 (Python) %o A076621 from sympy import prime, primerange %o A076621 def aupton(terms): %o A076621 primes = list(primerange(3, prime(terms+1)+1)) %o A076621 return [9] + [((p+q)//2)**2 for p, q in zip(primes[:-1], primes[1:])] %o A076621 print(aupton(43)) # _Michael S. Branicky_, Sep 16 2021 %Y A076621 Cf. A006094, A048761, A074927. %K A076621 nonn %O A076621 1,1 %A A076621 _Reinhard Zumkeller_, Oct 22 2002