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 A127678 a(n) = numerator of b(n), where b(1) = 1, b(n+1) = (sum{k=1 to n} b(k))/product{j=1 to n} b(j). 1

%I

%S 1,1,2,2,3,5,7,17,39,131,241,1843,33951,475103,66624833,17107028693,

%T 33453912854619,1200873381252944089,200445185648334612665809,

%U 14036199771684615424002710560757

%N a(n) = numerator of b(n), where b(1) = 1, b(n+1) = (sum{k=1 to n} b(k))/product{j=1 to n} b(j).

%F For n >= 4, b(n) = 1 +(b(n-1)-1)/b(n-2).

%t f[l_List] := Append[l, Plus @@ l/Times @@ l];Numerator[Nest[f, {1}, 20]] (* _Ray Chandler_, Feb 13 2007 *)

%Y Cf. A127679.

%K easy,frac,nonn

%O 1,3

%A _Leroy Quet_, Jan 23 2007

%E Extended by _Ray Chandler_, Feb 13 2007

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Last modified November 29 01:35 EST 2022. Contains 358421 sequences. (Running on oeis4.)