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A281013 Tetrangle T(n,k,i) = i-th part of k-th prime composition of n. 16
1, 2, 2, 1, 3, 2, 1, 1, 3, 1, 4, 2, 1, 1, 1, 2, 2, 1, 3, 1, 1, 3, 2, 4, 1, 5, 2, 1, 1, 1, 1, 2, 2, 1, 1, 3, 1, 1, 1, 3, 1, 2, 3, 2, 1, 4, 1, 1, 4, 2, 5, 1, 6, 2, 1, 1, 1, 1, 1, 2, 1, 2, 1, 1, 2, 2, 1, 1, 1, 2, 2, 2, 1, 3, 1, 1, 1, 1, 3, 1, 1, 2, 3, 1, 2, 1, 3, 2, 1, 1, 3, 2, 2, 3, 3, 1, 4, 1, 1, 1, 4, 1, 2, 4, 2, 1, 4, 3, 5, 1, 1, 5, 2, 6, 1, 7 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
The *-product of two or more finite sequences is defined to be the lexicographically minimal sequence obtainable by shuffling them together. Every finite positive integer sequence has a unique *-factorization using prime compositions P = {(1), (2), (21), (3), (211), ...}. See A060223 and A228369 for details.
These are co-Lyndon compositions, ordered first by sum and then lexicographically. - Gus Wiseman, Nov 15 2019
LINKS
FORMULA
Row lengths are A059966(n) = number of prime compositions of n.
EXAMPLE
The prime factorization of (1, 1, 4, 2, 3, 1, 5, 5) is: (11423155) = (1)*(1)*(5)*(5)*(4231). The prime factorizations of the initial terms of A000002 are:
(1) = (1)
(12) = (1)*(2)
(122) = (1)*(2)*(2)
(1221) = (1)*(221)
(12211) = (1)*(2211)
(122112) = (1)*(2)*(2211)
(1221121) = (1)*(221121)
(12211212) = (1)*(2)*(221121)
(122112122) = (1)*(2)*(2)*(221121)
(1221121221) = (1)*(221)*(221121)
(12211212212) = (1)*(2)*(221)*(221121)
(122112122122) = (1)*(2)*(2)*(221)*(221121).
Read as a sequence:
(1), (2), (21), (3), (211), (31), (4), (2111), (221), (311), (32), (41), (5).
Read as a triangle:
(1)
(2)
(21), (3)
(211), (31), (4)
(2111), (221), (311), (32), (41), (5).
Read as a sequence of triangles:
1 2 2 1 2 1 1 2 1 1 1 2 1 1 1 1 2 1 1 1 1 1
3 3 1 2 2 1 2 2 1 1 2 1 2 1 1
4 3 1 1 3 1 1 1 2 2 1 1 1
3 2 3 1 2 2 2 2 1
4 1 3 2 1 3 1 1 1 1
5 4 1 1 3 1 1 2
4 2 3 1 2 1
5 1 3 2 1 1
6 3 2 2
3 3 1
4 1 1 1
4 1 2
4 2 1
4 3
5 1 1
5 2
6 1
7.
MATHEMATICA
colynQ[q_]:=Array[Union[{RotateRight[q, #], q}]=={RotateRight[q, #], q}&, Length[q]-1, 1, And];
lexsort[f_, c_]:=OrderedQ[PadRight[{f, c}]];
Table[Sort[Select[Join@@Permutations/@IntegerPartitions[n], colynQ], lexsort], {n, 5}] (* Gus Wiseman, Nov 15 2019 *)
CROSSREFS
The binary version is A329318.
The binary non-"co" version is A102659.
A sequence listing all Lyndon compositions is A294859.
Numbers whose binary expansion is co-Lyndon are A328596.
Numbers whose binary expansion is co-Lyndon are A275692.
Binary Lyndon words are A001037.
Lyndon compositions are A059966.
Normal Lyndon words are A060223.
Sequence in context: A182490 A053274 A243926 * A190683 A181810 A339304
KEYWORD
nonn,tabf
AUTHOR
Gus Wiseman, Jan 12 2017
STATUS
approved

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Last modified May 21 09:41 EDT 2024. Contains 372733 sequences. (Running on oeis4.)