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A056235
n*2^(n*2^n+n)-1.
0
7, 2047, 402653183, 1180591620717411303423, 233840261972944466912589573234605283144949206876159
OFFSET
1,1
COMMENTS
For n>2, a(n) is base at which zero is reached for the function "write f(j) in base j, read as base j+1 and then subtract 1 to give f(j+1)" starting from f(n)=2n^2-1.
FORMULA
a(n) =A003261(A036289(n)) =A036289(n)*A001146(n)^n-1
EXAMPLE
a(3)=3*2^(3*2^3+3)-1=3*2^27-1=402653184-1=402653183
CROSSREFS
Sequence in context: A145253 A248730 A024099 * A139299 A004818 A125538
KEYWORD
nonn
AUTHOR
Henry Bottomley, Aug 06 2000
STATUS
approved