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A221132
a(n) = lcm(a(n-1), n^2 + n + 1) for n > 1 with a(1) = 1.
1
1, 7, 91, 273, 8463, 363909, 6914271, 504741783, 504741783, 18675445971, 18675445971, 2932045017447, 178854746064267, 37738351419560337, 9094942692114041217, 9094942692114041217, 2792147406479010653619, 136815222917471522027331
OFFSET
1,2
COMMENTS
Not the same as if a(n) = lcm(f(1),f(2),...,f(n))/3 with f(x)=x^2+x+1 and a(1)=f(1).
LINKS
MATHEMATICA
f[x_] := x^2 + x + 1; a[1] = 1; a[n_] := LCM[f[n], a[n - 1]]; Array[a, 18]
nxt[{n_, a_}]:={n+1, LCM[a, n^2+3n+3]}; NestList[nxt, {1, 1}, 20][[;; , 2]] (* Harvey P. Dale, Sep 22 2024 *)
CROSSREFS
Cf. A193181.
Sequence in context: A123694 A319978 A085026 * A181475 A374094 A249640
KEYWORD
nonn
AUTHOR
Robert G. Wilson v, Jan 02 2013
STATUS
approved