OFFSET
0,7
COMMENTS
T(n*(n+3)/2,n) = A227682(n).
From Vaclav Kotesovec, Sep 07 2014: (Start)
In general, column k is asymptotic to c(k) * 2^n. The constants c(k) numerically:
c(0) = 0.144394047543301210639449860964615390044455952420342... = A048651/2
c(1) = 0.231997216225445223894202367545783700531838988546098... = c(0)*A065442
c(2) = 0.104261929557371534733906196116707679501974368826074...
c(3) = 0.017956317806894073430249112172514186063327165575720...
c(4) = 0.001343254222922697613125145839110293324517874530073...
c(5) = 0.000046459767012163920051487037952792359225887287888...
c(6) = 0.000000768651747857094917953943327540619110335556499...
c(7) = 0.000000006200599904985793344094393321042983316604040...
c(8) = 0.000000000024656652167851516076173236693314090168122...
c(9) = 0.000000000000048633746319332356416193899916110113745...
c(10)= 0.000000000000000047750743608910618576944191079881479...
c(20)= 1.05217230403079700467566...*10^(-63)
For big k is c(k) ~ m * 2^(-k*(k+1)/2), where m = 1/(4*c(0)) = 1/(2*A048651) = 1.7313733097275318...
(End)
REFERENCES
M. Archibald, A. Blecher and A. Knopfmacher, Fixed points in compositions and words, accepted by the Journal of Integer Sequences.
LINKS
Joerg Arndt and Alois P. Heinz, Table of n, a(n) for n = 0..10010 (rows 0..140, flattened)
M. Archibald, A. Blecher, and A. Knopfmacher, Fixed Points in Compositions and Words, J. Int. Seq., Vol. 23 (2020), Article 20.11.1.
EXAMPLE
Triangle starts:
00: 1,
01: 0, 1,
02: 1, 1, 0,
03: 2, 1, 1, 0,
04: 3, 4, 1, 0, 0,
05: 6, 7, 3, 0, 0, 0,
06: 11, 16, 4, 1, 0, 0, 0,
07: 22, 29, 12, 1, 0, 0, 0, 0,
08: 42, 60, 23, 3, 0, 0, 0, 0, 0,
09: 82, 120, 47, 7, 0, 0, 0, 0, 0, 0,
10: 161, 238, 100, 12, 1, 0, 0, 0, 0, 0, 0,
11: 316, 479, 198, 30, 1, 0, 0, 0, 0, 0, 0, 0,
12: 624, 956, 404, 61, 3, 0, 0, 0, 0, 0, 0, 0, 0,
13: 1235, 1910, 818, 126, 7, 0, 0, 0, 0, 0, 0, 0, 0, 0,
14: 2449, 3817, 1652, 258, 16, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
15: 4864, 7633, 3319, 537, 30, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
...
From Gus Wiseman, Apr 03 2022: (Start)
Row n = 5 counts the following compositions (empty columns indicated by dots):
(5) (14) (113) . . .
(23) (32) (122)
(41) (131) (1211)
(212) (221)
(311) (1112)
(2111) (1121)
(11111)
(End)
MAPLE
b:= proc(n, i) option remember; `if`(n=0, 1, expand(
add(b(n-j, i+1)*`if`(i=j, x, 1), j=1..n)))
end:
T:= n-> (p-> seq(coeff(p, x, i), i=0..n))(b(n, 1)):
seq(T(n), n=0..15);
MATHEMATICA
b[n_, i_] := b[n, i] = If[n == 0, 1, Expand[Sum[b[n-j, i+1]*If[i == j, x, 1], {j, 1, n}]]]; T[n_] := Function[{p}, Table[Coefficient[p, x, i], {i, 0, n}]][b[n, 1]]; Table[T[n], {n, 0, 15}] // Flatten (* Jean-François Alcover, Jan 06 2015, after Alois P. Heinz *)
pq[y_]:=Length[Select[Range[Length[y]], #==y[[#]]&]];
Table[Length[Select[Join@@Permutations/@IntegerPartitions[n], pq[#]==k&]], {n, 0, 9}, {k, 0, n}] (* Gus Wiseman, Apr 03 2022 *)
CROSSREFS
Row sums are A011782.
Columns k=0-10 give: A238351, A240736, A240737, A240738, A240739, A240740, A240741, A240742, A240743, A240744, A240745.
The version for permutations is A008290.
The version with all zeros removed is A238350.
The version for reversed partitions is A238352.
Below: comps = compositions, first = column k=0, stat = rank statistic.
KEYWORD
nonn,tabl
AUTHOR
Joerg Arndt and Alois P. Heinz, Feb 25 2014
STATUS
approved