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%I #23 Dec 31 2023 12:37:06
%S 1,2,3,8,12,10,14,9,13,11,15,32,48,40,56,36,52,44,60,34,50,42,58,38,
%T 54,46,62,33,49,41,57,37,53,45,61,35,51,43,59,39,55,47,63,128,192,160,
%U 224,144,208,176,240,136,200,168,232,152,216,184,248,132,196,164,228,148,212
%N Consider the doubly-infinite permutation P defined on page 87 of Davis et al. (1977); sequence gives the terms starting at and to the right of 1.
%C P is a doubly-infinite sequence which is a permutation of the positive integers and contains no increasing or decreasing 4-term arithmetic progression.
%C A central portion of P, showing terms to the left (see A368358) and right (the present sequence) of the central 1:
%C ..., 18, 28, 20, 24, 16, 7, 5, 6, 4, 1, 2, 3, 8, 12, 10, 14, 9, 13, 11, 15, ...
%C See the link for a larger portion.
%H Davis, J. A.; Entringer, R. C.; Graham, R. L.; and Simmons, G. J.; <a href="http://matwbn.icm.edu.pl/ksiazki/aa/aa34/aa3417.pdf">On permutations containing no long arithmetic progressions</a>, Acta Arith. 34 (1977), no. 1, 81-90. The recurrence defining P is given in Fact 6 on page 87.
%H N. J. A. Sloane, <a href="/A368357/a368357.txt">A portion of P showing 511 consecutive terms around 1</a>
%H N. J. A. Sloane, <a href="/A368357/a368357_1.txt">Maple code</a>
%Y Cf. A003407, A368358 (the left-hand portion, reversed).
%K nonn
%O 0,2
%A _N. J. A. Sloane_, Dec 31 2023.