login
This site is supported by donations to The OEIS Foundation.
Logo

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A106177 Functional composition table for "n o m" = "n composed with m", where n and m are the "primal codes" of finite partial functions on the positive integers and 1 is the code for the empty function. 27
1, 1, 1, 1, 2, 1, 1, 3, 1, 1, 1, 1, 1, 4, 1, 1, 5, 2, 9, 1, 1, 1, 6, 1, 1, 1, 2, 1, 1, 7, 1, 25, 1, 3, 1, 1, 1, 1, 1, 36, 1, 2, 1, 8, 1, 1, 1, 1, 49, 1, 5, 1, 27, 1, 1, 1, 10, 3, 1, 1, 6, 1, 1, 1, 2, 1, 1, 11, 1, 1, 2, 7, 1, 125, 4, 3, 1, 1, 1, 3, 1, 100, 1, 1, 1, 216, 1, 1, 1, 4, 1, 1, 13 (list; table; graph; refs; listen; history; internal format)
OFFSET

1,5

COMMENTS

The right diagonal labeled by the prime power of the form j:k = (prime(j))^k contains the j^th power primes in the factorization raised to the k^th power. For example, the right diagonal labeled by the number 2 = 1:1 = (prime(1))^1 contains the power-free parts of each positive integer, specifically A055231 and the right diagonal labeled by the number 4 = 1:2 = (prime(1))^2 contains the squares of the squarefree parts of positive integers.

In general, then the right diagonal labeled by m = (j_i : k_i)_i = Product_i prime(j_i)^(k_i) contains the product over i of the (j_i)th power primes in the factorization raised to the (k_i)th powers.

For example, the operator 5 = 3:1 extracts the 3rd power primes in the factorization of each n and raises them to the first power, thus sending 8 = 1:3 to 2 = 1:1, 27 = 2:3 to 3 = 2:1 and so on.

EXAMPLE

` ` ` ` ` ` ` ` ` ` `n o m

` ` ` ` ` ` ` ` ` ` ` \ /

` ` ` ` ` ` ` ` ` ` `1 . 1

` ` ` ` ` ` ` ` ` ` \ / \ /

` ` ` ` ` ` ` ` ` `2 . 1 . 2

` ` ` ` ` ` ` ` ` \ / \ / \ /

` ` ` ` ` ` ` ` `3 . 1 . 1 . 3

` ` ` ` ` ` ` ` \ / \ / \ / \ /

` ` ` ` ` ` ` `4 . 1 . 2 . 1 . 4

` ` ` ` ` ` ` \ / \ / \ / \ / \ /

` ` ` ` ` ` `5 . 1 . 3 . 1 . 1 . 5

` ` ` ` ` ` \ / \ / \ / \ / \ / \ /

` ` ` ` ` `6 . 1 . 1 . 1 . 4 . 1 . 6

` ` ` ` ` \ / \ / \ / \ / \ / \ / \ /

` ` ` ` `7 . 1 . 5 . 2 . 9 . 1 . 1 . 7

` ` ` ` \ / \ / \ / \ / \ / \ / \ / \ /

` ` ` `8 . 1 . 6 . 1 . 1 . 1 . 2 . 1 . 8

` ` ` \ / \ / \ / \ / \ / \ / \ / \ / \ /

` ` `9 . 1 . 7 . 1 . 25. 1 . 3 . 1 . 1 . 9

` ` \ / \ / \ / \ / \ / \ / \ / \ / \ / \ /

` 10 . 1 . 1 . 1 . 36. 1 . 2 . 1 . 8 . 1 . 10

Primal codes of finite partial functions on positive integers:

1 = { }

2 = 1:1

3 = 2:1

4 = 1:2

5 = 3:1

6 = 1:1 2:1

7 = 4:1

8 = 1:3

9 = 2:2

10 = 1:1 3:1

11 = 5:1

12 = 1:2 2:1

13 = 6:1

14 = 1:1 4:1

15 = 2:1 3:1

16 = 1:4

17 = 7:1

18 = 1:1 2:2

19 = 8:1

20 = 1:2 3:1

CROSSREFS

Cf. A061396, A062504, A062537, A062860, A106178.

Sequence in context: A114118 A146014 A202241 * A135010 A138138 A196931

Adjacent sequences:  A106174 A106175 A106176 * A106178 A106179 A106180

KEYWORD

nonn,tabl

AUTHOR

Jon Awbrey (jawbrey(AT)att.net), May 23 2005

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
Recent Additions | More pages | Superseeker | Maintained by The OEIS Foundation Inc.

Content is available under The OEIS End-User License Agreement .

Last modified February 17 19:13 EST 2012. Contains 206085 sequences.