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 A073784 #11 Apr 01 2021 13:18:54
%S A073784 1,1,0,0,1,1,0,0,1,1,0,0,1,0,0,0,0,1,1,0,0,0,0,1,0,0,1,1,0,0,1,0,0,0,
%T A073784 0,1,0,0,0,0,1,1,0,0,0,0,1,0,0,1,1,0,0,0,0,1,0,0,1,0,0,0,0,1,0,0,0,0,
%U A073784 0,0,1,0,0,1,1,0,0,1,1,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,1,0,0,0,0,1,1,0
%N A073784 Number of primes between successive composite numbers.
%H A073784 Harvey P. Dale, <a href="/A073784/b073784.txt">Table of n, a(n) for n = 1..1000</a>
%e A073784 a(7) = 0 since there are no primes between the 7th and the 8th composites (14 and 15).
%t A073784 Composite[n_Integer] := FixedPoint[n + PrimePi[ # ] + 1 &, n + PrimePi[n] + 1]; Table[ PrimePi[Composite[n + 1]] - PrimePi[Composite[n]], {n, 105}] (* _Robert G. Wilson v_, Dec 20 2004 *)
%t A073784 Differences[Select[Range[300],CompositeQ]]-1 (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Apr 01 2021 *)
%Y A073784 a(n) = A073783(n) - 1.
%Y A073784 a(n) = A002808(n+1) - A002808(n) - 1.
%Y A073784 Also first differences of A073425.
%K A073784 easy,nonn
%O A073784 1,1
%A A073784 _Lior Manor_, Aug 11 2002