A123703 - OEIS

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A123703

a(1)=a(2)=1. For n >= 3, a(n) = |(product{k=1 to n-1} a(k)) - (sum{j=1 to n-1} a(j))|.

1, 1, 1, 2, 3, 2, 2, 12, 264, 75744, 5758891776, 33165272341980979200, 1099935289708766240667530888404210286592, 1209857641546707521062997518664689369471121315619387834957574646785625397657600

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,4

LINKS

Table of n, a(n) for n=1..14.

MATHEMATICA

f[l_List] := Append[l, Abs[Times @@ l - Plus @@ l]]; Nest[f, {1, 1}, 12] (* Ray Chandler, Oct 09 2006 *)

CROSSREFS

Cf. A123702.

Sequence in context: A298310 A138680 A171684 * A105436 A266911 A244075

Adjacent sequences: A123700 A123701 A123702 * A123704 A123705 A123706

KEYWORD

easy,nonn

AUTHOR

Leroy Quet, Oct 08 2006

EXTENSIONS

Extended by Ray Chandler, Oct 09 2006

STATUS

approved