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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. +0
28
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; listen)
OFFSET

1,5

COMMENT

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 square-free 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: A147867 A114118 A146014 this_sequence A135010 A138138 A080209

Adjacent sequences: A106174 A106175 A106176 this_sequence A106178 A106179 A106180

KEYWORD

nonn,tabl

AUTHOR

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

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Last modified November 23 17:09 EST 2009. Contains 167438 sequences.


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