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 A097824 #6 Jun 03 2012 12:33:38 %S A097824 12,12,4,52,52,72,96,198,198,114,594,48,354,1860,3942,2574,2574,2574, %T A097824 20910,20910,9600,9600,152250,152250,152250,152250,1887270,4667040, %U A097824 4094790 %N A097824 Gaps associated with the arithmetic progressions of semiprimes in A096003. %C A097824 The terms a(1),a(2) and a(3) are omitted to avoid the ambiguity caused by the two progressions of length 3 ending at A096003(3)=14: a(3)=5 for (4,9,14) or a(3)=4 for (6,10,14). %e A097824 a(6)=4 because the 6 semiprimes in the progression ending at A096003(6)=221 are separated by an increment of 4: 201=3*67, 205=5*41, 209=11*19, 213=3*71, 217=7*31, 221=13*17. %Y A097824 Cf. A096003, A093364 gaps in arithmetic progressions of primes, A082919 clusters of 8 consecutive semiprimes. %K A097824 more,nonn %O A097824 4,1 %A A097824 _Hugo Pfoertner_, Aug 27 2004 %E A097824 a(26)-a(30) from _Hugo Pfoertner_, Sep 07 2004 %E A097824 a(31)-a(32) from _Donovan Johnson_, Jun 03 2012