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 A090781 #13 May 16 2021 07:58:12
%S A090781 5,16,21,24,40,45,48,96,112,117,144,160,165,192,264,280,285,288,336,
%T A090781 352,357,504,520,525,648,816,832,837,936,952,957,1152,1344,1360,1365,
%U A090781 1368,1440,1656,1672,1677,1752,1824,1840,1845,1872,1968,2184,2200,2205,2328
%N A090781 Numbers that can be expressed as the difference of the squares of primes in just one distinct way.
%H A090781 T. D. Noe, <a href="/A090781/b090781.txt">Table of n, a(n) for n=1..908</a>
%e A090781 5 = 3^2 - 2^2.
%t A090781 With[{nn=100},Take[Sort[Transpose[Select[Tally[Last[#]-First[#]&/@ Subsets[ Prime[Range[nn]]^2,{2}]],Last[#]==1&]][[1]]],nn]] (* _Harvey P. Dale_, Apr 05 2014 *)
%o A090781 (Python)
%o A090781 from sympy import primerange
%o A090781 from collections import Counter
%o A090781 def aupto(limit):
%o A090781 sqps = [p*p for p in primerange(1, limit//2+1)]
%o A090781 ways = Counter(b-a for i, a in enumerate(sqps) for b in sqps[i+1:])
%o A090781 return sorted(k for k in ways if k <= limit and ways[k] == 1)
%o A090781 print(aupto(2328)) # _Michael S. Branicky_, May 16 2021
%Y A090781 Cf. A078667, A090788, A090782, A090785.
%K A090781 nonn
%O A090781 1,1
%A A090781 _Ray Chandler_, Feb 14 2004