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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.

A325680 Number of compositions of n such that every distinct circular subsequence has a different sum.

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%I A325680 #13 Jun 19 2021 22:28:56
%S A325680 1,1,2,4,5,6,8,14,16,29,24,42,46,78,66,146,133,242,208,386,352,620,
%T A325680 494,948,842,1447
%N A325680 Number of compositions of n such that every distinct circular subsequence has a different sum.
%C A325680 A composition of n is a finite sequence of positive integers summing to n.
%C A325680 A circular subsequence is a sequence of consecutive terms where the first and last parts are also considered consecutive.
%e A325680 The a(1) = 1 through a(8) = 16 compositions:
%e A325680   (1)  (2)   (3)    (4)     (5)      (6)       (7)        (8)
%e A325680        (11)  (12)   (13)    (14)     (15)      (16)       (17)
%e A325680              (21)   (22)    (23)     (24)      (25)       (26)
%e A325680              (111)  (31)    (32)     (33)      (34)       (35)
%e A325680                     (1111)  (41)     (42)      (43)       (44)
%e A325680                             (11111)  (51)      (52)       (53)
%e A325680                                      (222)     (61)       (62)
%e A325680                                      (111111)  (124)      (71)
%e A325680                                                (142)      (125)
%e A325680                                                (214)      (152)
%e A325680                                                (241)      (215)
%e A325680                                                (412)      (251)
%e A325680                                                (421)      (512)
%e A325680                                                (1111111)  (521)
%e A325680                                                           (2222)
%e A325680                                                           (11111111)
%t A325680 subalt[q_]:=Union[ReplaceList[q,{___,s__,___}:>{s}],DeleteCases[ReplaceList[q,{t___,__,u___}:>{u,t}],{}]];
%t A325680 Table[Length[Select[Join@@Permutations/@IntegerPartitions[n],UnsameQ@@Total/@subalt[#]&]],{n,0,15}]
%Y A325680 Cf. A000079, A008965, A108917, A143823, A169942, A276024.
%Y A325680 Cf. A325545, A325676, A325682, A325685, A325687, A325688.
%K A325680 nonn,more
%O A325680 0,3
%A A325680 _Gus Wiseman_, May 13 2019
%E A325680 a(18)-a(25) from _Robert Price_, Jun 19 2021