This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A362500 #9 Apr 23 2023 12:18:03
%S A362500 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 A362500 17,23,24,27,28,37,34,43,43,51,51,66,63,80,78,97,97,122,116,150,146,
%U A362500 183,179,229,220,277,276,344,337,430,413,528,516,652,635
%N A362500 Number of symmetric compositions of n where differences between adjacent parts are in {-1,1}.
%C A362500 a(n) and A173258(n) have the same parity.
%H A362500 John Tyler Rascoe, <a href="/A362500/a362500_1.txt">Python program</a>
%e A362500 The a(9) = 2 through a(14) = 6 compositions:
%e A362500 (9) (10) (11) (12) (13) (14)
%e A362500 (12321) (343) (434) (23232) (454) (545)
%e A362500 (1212121) (32123) (32323) (23432)
%e A362500 (2121212) (2123212) (1232321)
%e A362500 (121212121) (3212123)
%e A362500 (212121212)
%o A362500 (Python) # see linked program
%Y A362500 Cf. A016116 (symmetric compositions).
%Y A362500 Cf. A173258 (compositions where differences between adjacent parts are in {-1,1}).
%Y A362500 Cf. A003242, A350837.
%K A362500 nonn
%O A362500 0,5
%A A362500 _John Tyler Rascoe_, Apr 22 2023