A135599 Word obtained from axiom 2 using the morphism 1-> 267, 2-> 13467, 3-> 247, 4-> 23567, 5-> 467, 6-> 12457, 7-> 123456.

1, 3, 4, 6, 7, 1, 2, 4, 5, 7, 1, 2, 3, 4, 5, 6, 1, 3, 4, 6, 7, 2, 3, 5, 6, 7, 1, 2, 3, 4, 5, 6, 1, 3, 4, 6, 7, 2, 4, 7, 4, 6, 7, 1, 2, 4, 5, 7, 1, 2, 3, 4, 5, 6, 2, 6, 7, 1, 3, 4, 6, 7, 2, 3, 5, 6, 7, 4, 6, 7, 1, 2, 3, 4, 5, 6, 2, 6, 7, 1, 3, 4, 6, 7, 2, 4, 7, 2, 3, 5, 6, 7, 4, 6, 7, 1, 2, 4, 5, 7, 1, 3, 4, 6, 7

Offset: 1

Author

Roger L. Bagula, Feb 26 2008

Keywords

• nonn
• easy
• less

Comments

Previous name was: Seven-tone substitution on a Fano projective plane graph as used in A120714 (for use in making church tone A,B,C,D,E,F,G music).

Idea inspired by a post in yahoo egroup fractals by "Dahlia Lahla" astro_girl_690(AT)yahoo.ca

In Mathematica you can transfer this to a 12-tone MIDI scale as: to letters

b = a /. 1 -> "a" /. 2 -> "b" /. 3 -> "c" /. 4 -> "d" /. 5 -> "e" /. 6 -> "f" /. 7 -> "g"

back to numbers on a 12-tone scale:

c = b /. "a" -> 1 /. "b" -> 3 /. "c" -> 4 /. "d" -> 6 /. "e" -> 8 /. "f" -> 9 /. "g" -> 11

Links

• Roger L. Bagula, Feb 26 2008, Table of n, a(n) for n = 1..314

Crossrefs

Cf. A120714.

Programs

Mathematica

s[1] = {2, 6, 7}; s[2] = {1, 3, 4, 6, 7}; s[3] = {2, 4, 7}; s[4] = {2, 3, 5, 6, 7}; s[5] = {4, 6, 7}; s[6] = {1, 2, 4, 5, 7}; s[7] = {1, 2, 3, 4, 5, 6};
t[a_] := Flatten[s /@ a];
p[0] = s[1]; p[1] = t[p[0]]; p[n_] := t[p[n - 1]]; a = p[3]

Extensions

Edited and new name from Joerg Arndt, Sep 26 2018