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A000743 Number of compositions of n into 5 ordered relatively prime parts.
(Formerly M3852 N1577)
4
1, 5, 15, 35, 70, 125, 210, 325, 495, 700, 1000, 1330, 1820, 2305, 3060, 3750, 4830, 5775, 7315, 8490, 10625, 12155, 14880, 16835, 20475, 22620, 27405, 30100, 35750, 39100, 46360, 49655, 58905, 62985, 73320, 78340, 91390, 95720, 111930, 117425 (list; graph; refs; listen; history; text; internal format)
OFFSET

3,2

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

Table of n, a(n) for n=3..42.

H. W. Gould, Binomial coefficients, the bracket function and compositions with relatively prime summands, Fib. Quart. 2(4) (1964), 241-260.

N. J. A. Sloane, Transforms

FORMULA

Möbius transform of binomial(n-1, 4).

MATHEMATICA

a[n_] := With[{m=n+2}, Sum[Boole[Divisible[m, k]] MoebiusMu[m/k] Binomial[ k-1, 4] , {k, 1, m}]]; Table[a[n], {n, 3, 50}] (* Jean-François Alcover, Feb 11 2016 *)

CROSSREFS

Sequence in context: A015622 A000750 A008487 * A138779 A090580 A000332

Adjacent sequences:  A000740 A000741 A000742 * A000744 A000745 A000746

KEYWORD

nonn

AUTHOR

N. J. A. Sloane.

STATUS

approved

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Last modified June 25 19:53 EDT 2017. Contains 288729 sequences.