%I #9 Apr 23 2023 12:18:03
%S 1,1,1,1,2,2,1,3,3,2,3,4,2,5,6,3,5,7,5,8,8,8,8,12,10,12,14,15,16,21,
%T 17,23,24,27,28,37,34,43,43,51,51,66,63,80,78,97,97,122,116,150,146,
%U 183,179,229,220,277,276,344,337,430,413,528,516,652,635
%N Number of symmetric compositions of n where differences between adjacent parts are in {-1,1}.
%C a(n) and A173258(n) have the same parity.
%H John Tyler Rascoe, <a href="/A362500/a362500_1.txt">Python program</a>
%e The a(9) = 2 through a(14) = 6 compositions:
%e (9) (10) (11) (12) (13) (14)
%e (12321) (343) (434) (23232) (454) (545)
%e (1212121) (32123) (32323) (23432)
%e (2121212) (2123212) (1232321)
%e (121212121) (3212123)
%e (212121212)
%o (Python) # see linked program
%Y Cf. A016116 (symmetric compositions).
%Y Cf. A173258 (compositions where differences between adjacent parts are in {-1,1}).
%Y Cf. A003242, A350837.
%K nonn
%O 0,5
%A _John Tyler Rascoe_, Apr 22 2023
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