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 A000741 Number of compositions of n into 3 ordered relatively prime parts. (Formerly M2531 N0999) 7
 0, 0, 1, 3, 6, 9, 15, 18, 27, 30, 45, 42, 66, 63, 84, 84, 120, 99, 153, 132, 174, 165, 231, 180, 270, 234, 297, 270, 378, 276, 435, 360, 450, 408, 540, 414, 630, 513, 636, 552, 780, 558, 861, 690, 828, 759, 1035, 744, 1113, 870, 1104, 972, 1326, 945, 1380, 1116, 1386, 1218 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,4 REFERENCES H. W. Gould, Binomial coefficients, the bracket function and compositions with relatively prime summands, Fib. Quart. 2 (1964), 241-260. 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 Alois P. Heinz, Table of n, a(n) for n = 1..10000 C. Kimberling, Matrix Transformations of Integer Sequences, J. Integer Seqs., Vol. 6, 2003. N. J. A. Sloane, Transforms FORMULA Moebius transform of A000217(n-2). MAPLE with (numtheory): mobtr:= proc(p)           proc(n) option remember;             add (mobius(n/d)*p(d), d=divisors(n))           end         end: A000217:= n-> n*(n+1)/2: a:= mobtr (n-> A000217(n-2)): seq (a(n), n=1..58);  # Alois P. Heinz, Feb 08 2011 CROSSREFS Sequence in context: A146562 A179893 A133331 * A133205 A049991 A143981 Adjacent sequences:  A000738 A000739 A000740 * A000742 A000743 A000744 KEYWORD nonn,easy AUTHOR EXTENSIONS Edited by Alois P. Heinz, Feb 08 2011 STATUS approved

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