# Greetings from The On-Line Encyclopedia of Integer Sequences! http://oeis.org/ Search: id:a325682 Showing 1-1 of 1 %I A325682 #11 Jun 19 2021 22:29:05 %S A325682 1,2,3,4,4,6,7,9,13,12,17,21,28,26,49,46,74,68,113,107,176,144,255, %T A325682 235,375 %N A325682 Number of necklace compositions of n such that every distinct circular subsequence has a different sum. %C A325682 A necklace composition of n is a finite sequence of positive integers summing to n that is lexicographically minimal among all of its cyclic rotations. %C A325682 A circular subsequence is a sequence of consecutive terms where the first and last parts are also considered consecutive. %e A325682 The a(1) = 1 through a(8) = 13 necklace compositions: %e A325682 (1) (2) (3) (4) (5) (6) (7) (8) %e A325682 (11) (12) (13) (14) (15) (16) (17) %e A325682 (111) (22) (23) (24) (25) (26) %e A325682 (1111) (11111) (33) (34) (35) %e A325682 (222) (124) (44) %e A325682 (111111) (142) (125) %e A325682 (1111111) (152) %e A325682 (2222) %e A325682 (11111111) %t A325682 neckQ[q_]:=Array[OrderedQ[{q,RotateRight[q,#]}]&,Length[q]-1,1,And]; %t A325682 subalt[q_]:=Union[ReplaceList[q,{___,s__,___}:>{s}],DeleteCases[ReplaceList[q,{t___,__,u___}:>{u,t}],{}]]; %t A325682 Table[Length[Select[Join@@Permutations/@IntegerPartitions[n],neckQ[#]&&UnsameQ@@Total/@subalt[#]&]],{n,20}] %Y A325682 Cf. A000079, A000740, A008965, A059966, A108917, A143823, A169942, A276024. %Y A325682 Cf. A325676, A325680, A325685, A325687. %K A325682 nonn,more %O A325682 1,2 %A A325682 _Gus Wiseman_, May 13 2019 %E A325682 a(21)-a(25) from _Robert Price_, Jun 19 2021 # Content is available under The OEIS End-User License Agreement: http://oeis.org/LICENSE