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A376044
a(0)=1; thereafter, a(n) = denominator of Sum_{i=1..n} A376043(i)/A376043(i+1).
1
1, 2, 10, 510, 13265610, 4577322365983258710, 7229483538732297474207602559153795628052249733810
OFFSET
0,2
LINKS
N. J. A. Sloane, A Nasty Surprise in a Sequence and Other OEIS Stories, Experimental Mathematics Seminar, Rutgers University, Oct 10 2024, Youtube video; Slides [Mentions this sequence]
FORMULA
a(0)=1; for n>0, a(n) = A376043(n)*a(n-1)^2 + a(n-1)).
More directly, a(n) = Prod_(i=0..n-1} A376043(i).
- N. J. A. Sloane, Sep 12 2024
MATHEMATICA
s[1] = 1; s[n_] := s[n] = 1 + Floor[s[n-1]/(1 - Sum[s[i-1]/s[i], {i, 2, n-1}])]; a[0] = 1; a[n_] := Denominator[Sum[s[i]/s[i+1], {i, 1, n}]]; Array[a, 7, 0] (* Amiram Eldar, Sep 08 2024 *)
CROSSREFS
Cf. A376043.
Sequence in context: A334286 A265627 A112449 * A011824 A064300 A290060
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Sep 07 2024
STATUS
approved