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A279198 Number of pairs of conjugate inseparable solutions of X + Y = 2Z (integer, disjoint triples from {1,2,3,...,3n}). 6

%I

%S 0,0,0,2,7,52,297,1994,14594,113794,991741,9199390,94105010,

%T 1015012796,11914379971,146974330141,1954701366709

%N Number of pairs of conjugate inseparable solutions of X + Y = 2Z (integer, disjoint triples from {1,2,3,...,3n}).

%D R. K. Guy, Sedlacek's Conjecture on Disjoint Solutions of x+y= z, Univ. Calgary, Dept. Mathematics, Research Paper No. 129, 1971.

%D R. K. Guy, Sedlacek's Conjecture on Disjoint Solutions of x+y= z, in Proc. Conf. Number Theory. Pullman, WA, 1971, pp. 221-223.

%D R. K. Guy, Packing [1,n] with solutions of ax + by = cz; the unity of combinatorics, in Colloq. Internaz. Teorie Combinatorie. Rome, 1973, Atti Conv. Lincei. Vol. 17, Part II, pp. 173-179, 1976.

%D Nowakowski, Richard Joseph, Generalization of the Langford-Skolem problem, MS Thesis, University of Calgary, 1975.

%H R. K. Guy, Letter to N. J. A. Sloane, June 24 1971: <a href="/A002572/a002572.jpg">front</a>, <a href="/A002572/a002572_1.jpg">back</a> [Annotated scanned copy, with permission] See sequence "J".

%H R. J. Nowakowski, <a href="/A104429/a104429.pdf">Generalizations of the Langford-Skolem problem</a>, M.S. Thesis, Dept. Math., Univ. Calgary, May 1975. [Scanned copy, with permission.]

%F A279197(n) + 2*A279198(n) = A202705(n).

%e Richard Guy gives examples in his letter.

%Y All of A279197, A279198, A202705, A279199, A104429, A282615 are concerned with counting solutions to X+Y=2Z in various ways.

%Y See also A002848, A002849.

%K nonn,more

%O 1,4

%A _N. J. A. Sloane_, Dec 15 2016

%E a(7)-a(16) from _Fausto A. C. Cariboni_, Feb 27 2017

%E a(17) from _Fausto A. C. Cariboni_, Mar 22 2017

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Last modified November 15 13:56 EST 2019. Contains 329149 sequences. (Running on oeis4.)