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A143765
a(n+1) = a(n)^2 - 3*n*a(n) + n^2, a(1) = 1.
6
1, -1, 11, 31, 605, 356975, 127424725111, 16237060566937994735039, 263642135854412795003324875413502371940690649, 69507175797876652622009028770643203522181284529919017784559264153993383198392412717393759
OFFSET
1,3
COMMENTS
Let f(n+1,k) = f(n,k)^2 + k*n*f(n,k) + n^2, f(1, k) = 1:
f(n,0)=A143760(n), f(n,-1)=A143761(n), f(n,+1)=A143762(n),
f(n,-2)=A143763(n), f(n,+2)=A143764(n), f(n,-3)=a(n), f(n,+3)=A143766(n).
FORMULA
a(n) ~ c^(2^n), where c = 1.22112407764058519321076802441458002508833724488233983960016657090909521541... . - Vaclav Kotesovec, Dec 18 2014
MATHEMATICA
RecurrenceTable[{a[n+1] == a[n]^2 - 3*n*a[n] + n^2, a[1] == 1}, a, {n, 1, 10}] (* Vaclav Kotesovec, Dec 18 2014 *)
CROSSREFS
Sequence in context: A163763 A201808 A111015 * A023306 A068839 A228530
KEYWORD
sign
AUTHOR
Reinhard Zumkeller, Sep 01 2008
STATUS
approved