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A002022 Pile of coconuts problem.
(Formerly M4305 N1800)
4
0, 6, 240, 1020, 78120, 279930, 40353600, 134217720, 31381059600, 99999999990, 34522712143920, 106993205379060, 51185893014090744, 155568095557812210, 98526125335693359360, 295147905179352825840, 239072435685151324847136 (list; graph; refs; listen; history; text; internal format)
OFFSET

2,2

REFERENCES

N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).

N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

LINKS

T. D. Noe, Table of n, a(n) for n = 2..100

Santo D'Agostino, “The Coconut Problem”; Updated With Solution, May 2011.

R. S. Underwood and Robert E. Moritz, Problem 3242, Amer. Math. Monthly, 35 (1928), 47-48.

Ben Ames Williams, Coconuts Problem

MAPLE

f := proc(n) if n mod 2 = 1 then RETURN((n-1)^n-(n-1)) else RETURN((n-1)^(n+1)-(n-1)) fi; end:

MATHEMATICA

Rest[Table[If[OddQ[n], (n-1)^n-(n-1), (n-1)^(n+1)-(n-1)], {n, 30}]] (* Harvey P. Dale, Oct 21 2011 *)

CROSSREFS

Cf. A002021, A006091.

Sequence in context: A235346 A077231 A172965 * A065948 A052510 A234633

Adjacent sequences:  A002019 A002020 A002021 * A002023 A002024 A002025

KEYWORD

nonn,easy,nice

AUTHOR

N. J. A. Sloane.

EXTENSIONS

Formula and more terms from James A. Sellers, Feb 10 2000

STATUS

approved

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Last modified December 18 18:34 EST 2018. Contains 318243 sequences. (Running on oeis4.)