A105313 Triangle read by rows, based on the morphism f: 1->432, 2->431, 3->421, 4->321. First row is 1. If current row is a,b,c,..., then the next row is a,b,c,...,f(a),f(b),f(c),...

1, 1, 4, 3, 2, 1, 4, 3, 2, 4, 3, 2, 3, 2, 1, 4, 2, 1, 4, 3, 1, 1, 4, 3, 2, 4, 3, 2, 3, 2, 1, 4, 2, 1, 4, 3, 1, 4, 3, 2, 3, 2, 1, 4, 2, 1, 4, 3, 1, 3, 2, 1, 4, 2, 1, 4, 3, 1, 4, 2, 1, 4, 3, 1, 4, 3, 2, 3, 2, 1, 4, 3, 1, 4, 3, 2, 3, 2, 1, 4, 2, 1, 4, 3, 2, 1, 4, 3, 2, 4, 3, 2, 3, 2, 1, 4, 2, 1, 4, 3, 1, 4, 3, 2, 3

Offset

0,3

Links

Table of n, a(n) for n=0..104.

Mathematica

s[1] = {4, 3, 2}; s[2] = {4, 3, 1}; s[3] = {4, 2, 1}; s[4] = {3, 2, 1};
t[a_] := Join[a, Flatten[s /@ a]];
p[0] = {1}; p[1] = t[{1}]; p[n_] := t[p[n - 1]]
aa = Flatten[Table[p[n], {n, 0, 4}]]

Crossrefs

Sequence in context: A388476 A388492 A106655 * A085064 A030587 A194764

Adjacent sequences: A105310 A105311 A105312 * A105314 A105315 A105316

Keyword

nonn,tabf

Author

Roger L. Bagula, Apr 25 2005

Extensions

Revised by Sean A. Irvine, Feb 10 2026

Status

approved