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 A076843 #9 Jul 20 2014 14:41:40
%S A076843 1,1,1,1,1,5,15,27,261,2059,53321,3826345,599717165,344730727333,
%T A076843 4379034727152233,1299571503802595847199,9181632264980134793594508931,
%U A076843 32308854341042109701936418652172579113,67117797048843876734329361265492957492346044762131
%N A076843 Denominators of sequence of fractions defined by a(1) = a(2) = 1; for n > 2, a(n) = (a(n-1)+a(n-2)+1)/a(n-2).
%e A076843 1, 1, 3, 5, 3, 9/5, 29/15, 71/27, 751/261, 5095/2059, 117707/53321, ...
%p A076843 a := 1; b := 1; f := proc(n) option remember; global a,b; if n=1 then RETURN(a); fi; if n=2 then RETURN(b); fi; RETURN((f(n-1)+f(n-2)+1)/f(n-2)); end;
%t A076843 Denominator[RecurrenceTable[{a[1]==a[2]==1,a[n]==(a[n-1]+a[n-2]+1)/ a[n-2]},a,{n,20}]] (* _Harvey P. Dale_, Jul 20 2014 *)
%Y A076843 Cf. A076842, A076844.
%K A076843 nonn,frac
%O A076843 1,6
%A A076843 _N. J. A. Sloane_, Nov 21 2002