cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

User: Liangzhou Chen

Liangzhou Chen's wiki page.

Liangzhou Chen has authored 1 sequences.

A347717 Number of states of the minimal deterministic finite automaton that accepts ternary strings that represent numbers that are divisible by n.

Original entry on oeis.org

1, 2, 2, 4, 5, 3, 7, 8, 3, 10, 11, 5, 13, 14, 6, 16, 17, 4, 19, 20, 8, 22, 23, 9, 25, 26, 4, 28, 29, 11, 31, 32, 12, 34, 35, 6, 37, 38, 14, 40, 41, 15, 43, 44, 7, 46, 47, 17, 49, 50, 18, 52, 53, 5, 55, 56, 20, 58, 59, 21, 61, 62, 9, 64, 65, 23, 67, 68, 24, 70, 71, 10, 73
Offset: 1

Author

Liangzhou Chen, Sep 10 2021

Keywords

Comments

a(n) = n for all n coprime to 3.

Examples

			The minimal DFA when n=6, giving the form of transition table:
+-------+-----------+
|       | tr. func. |
| state +---+---+---+
|       | 0 | 1 | 2 |
+-------+---+---+---+
|->*A   | A | C | B | (mod 6 = 0)
+-------+---+---+---+
|   B   | A | C | B | (mod 6 = 2,4)
+-------+---+---+---+
|   C   | C | B | C | (mod 6 = 1,3,5)
+-------+---+---+---+
		

Crossrefs

Programs

  • PARI
    a(n) = n / 3^valuation(n, 3) + valuation(n, 3)

Formula

a(1) = 1, a(2) = 2, a(3n) = a(n) + 1, a(3n+1) = 3n+1, a(3n+2) = 3n+2.