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 A128296 a(n) = denominator of b(n): b(1)=1; b(n+1) = b(n) * [b(1);b(2),...,b(n)], where [...] is a continued fraction of rational terms. 2

%I

%S 1,1,1,3,99,1917729,695291630330558547,

%T 2868367896364283363830544991834226772439236224131

%N a(n) = denominator of b(n): b(1)=1; b(n+1) = b(n) * [b(1);b(2),...,b(n)], where [...] is a continued fraction of rational terms.

%C a(9) and a(10) have 129 and 341 digits, respectively and are too large to include here. - _R. J. Mathar_, Oct 08 2007

%e a(5) = the denominator of b(5). b(5) = (10/3) * (1 +1/(1 +1/(2 +3/10))) = 560/99.

%p L2cfrac := proc(L) local a,i; a := op(-1,L) ; for i from 2 to nops(L) do a := op(-i,L)+1/a ; od: RETURN(a) ; end: A128296 := proc() local b,n,bnxt; b :=  ; for n from 2 to 10 do bnxt := op(-1,b)*L2cfrac(b) ; b := [op(b),bnxt] ; od: [seq( denom(b[i]),i=1..nops(b))] ; end: A128296() ; # _R. J. Mathar_, Oct 08 2007

%Y Cf. A128295.

%K frac,nonn

%O 1,4

%A _Leroy Quet_, Feb 25 2007

%E More terms from _R. J. Mathar_, Oct 08 2007

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Last modified October 6 16:34 EDT 2022. Contains 357270 sequences. (Running on oeis4.)