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A166999
a(n) = a(n-1) + a(n-1)^2 + a(n-1)^3 for n>0 with a(0)=1.
1
1, 3, 39, 60879, 225636660844959, 11487591726386681145142587842614325062822719
OFFSET
0,2
FORMULA
Row sums of triangle A166880, which lists the coefficients in the iterations of x+x^2+x^3.
MATHEMATICA
NestList[#+#^2+#^3&, 1, 5] (* Harvey P. Dale, Sep 22 2024 *)
PROG
(PARI) a(n)=if(n==0, 1, a(n-1)+a(n-1)^2+a(n-1)^3)
CROSSREFS
Cf. A166880.
Sequence in context: A367033 A097421 A180418 * A319955 A317484 A196159
KEYWORD
nonn
AUTHOR
Paul D. Hanna, Nov 21 2009
STATUS
approved