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A110386
a(1) = 1, a(2) = a(1) + 1, a(3) = a(2)^2 + a(2) + 1; a(n + 1) = a(n)^n + a(n)^(n-1) + ... + a(n)^2 + a(n) + 1 = {a(n)^(n + 1)-1}/{a(n) - 1}.
1
1, 2, 7, 400, 25664160401, 11133592066966265230223312802560009320400030085606006
OFFSET
1,2
COMMENTS
The next term is too large to include.
EXAMPLE
a(3) = 2^2 + 2 + 1 = 7.
MAPLE
a[1]:=1: for n from 1 to 7 do a[n+1]:=sum(a[n]^j, j=0..n) od: seq(a[n], n=1..7); # Emeric Deutsch, Jul 31 2005
CROSSREFS
Sequence in context: A081505 A176748 A262088 * A260229 A321134 A027732
KEYWORD
easy,nonn
AUTHOR
Amarnath Murthy, Jul 26 2005
EXTENSIONS
More terms from Emeric Deutsch, Jul 31 2005
STATUS
approved