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A005166 a(0) = 1; a(n) = (1 + a(0)^3 + ... + a(n-1)^3)/n (not always integral!).
(Formerly M1551)
6
1, 2, 5, 45, 22815, 2375152056927, 2233176271342403475345148513527359103 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,2
COMMENTS
Terms are integers until n=A097398(2,2)=89.
Guy states that by computing the sequence modulo 89 it is easy to show that a(89) is not integral. - T. D. Noe, Sep 17 2007
REFERENCES
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
LINKS
R. K. Guy, Letter to N. J. A. Sloane, Sep 25 1986.
R. K. Guy, The strong law of small numbers. Amer. Math. Monthly 95 (1988), no. 8, 697-712.
R. K. Guy, The strong law of small numbers. Amer. Math. Monthly 95 (1988), no. 8, 697-712. [Annotated scanned copy]
Alex Stone, The Astonishing Behavior of Recursive Sequences, Quanta Magazine, Nov 16 2023, 13 pages.
Eric Weisstein's World of Mathematics, Goebel's Sequence.
CROSSREFS
Cf. A108394.
Sequence in context: A334252 A307147 A056680 * A121621 A225147 A119715
KEYWORD
nonn,easy,nice
AUTHOR
STATUS
approved

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Last modified February 24 15:13 EST 2024. Contains 370305 sequences. (Running on oeis4.)