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Revision History for A353333 (Bold, blue-underlined text is an addition; faded, red-underlined text is a deletion.)

Showing entries 1-10 | older changes
Number of ways to write n as a product of the terms of A340784 larger than 1; a(1) = 1 by convention (an empty product).
(history; published version)
#23 by Michael De Vlieger at Fri Apr 15 10:33:20 EDT 2022
STATUS

proposed

approved

#22 by Antti Karttunen at Fri Apr 15 09:37:33 EDT 2022
STATUS

editing

proposed

#21 by Antti Karttunen at Fri Apr 15 05:43:23 EDT 2022
LINKS

Antti Karttunen, <a href="/A353333/b353333.txt">Table of n, a(n) for n = 1..65537</a>

STATUS

approved

editing

#20 by N. J. A. Sloane at Fri Apr 15 00:38:15 EDT 2022
STATUS

editing

approved

#19 by N. J. A. Sloane at Fri Apr 15 00:38:13 EDT 2022
NAME

Number of ways to write n as a product of the terms of A340784 larger than one1; a(1) = 1 by convention (an empty product).

STATUS

approved

editing

#18 by N. J. A. Sloane at Thu Apr 14 16:42:34 EDT 2022
STATUS

proposed

approved

#17 by Antti Karttunen at Thu Apr 14 16:06:36 EDT 2022
STATUS

editing

proposed

Discussion
Thu Apr 14
16:42
N. J. A. Sloane: Thank you
#16 by Antti Karttunen at Thu Apr 14 16:06:22 EDT 2022
NAME

Number of ways to write n as a product of the terms of A340784 larger than one; a(1) = 1 by convention (an empty product).

Discussion
Thu Apr 14
16:06
Antti Karttunen: Better now?
#15 by Antti Karttunen at Thu Apr 14 16:04:39 EDT 2022
NAME

Number of ways to write n as a product of the terms of A340784 that are larger than one.

COMMENTS

Number of factorizations of n into terms of A340784 that are larger than one.

#14 by Antti Karttunen at Thu Apr 14 16:03:00 EDT 2022
EXAMPLE

Of the 11 eleven divisors of 220 larger than one, only [4, 10, 22, 55, 220] are in A340784, as both the number of their prime factors (with repetition, A001222), [2, 2, 2, 2, 4], and their integer pseudo logarithms (A056239), [2, 4, 6, 8, 10], are even. Using these factors gives the following possible factorizations: 220 = 10*22 = 4*10 = 55, *4, therefore a(220) = 3.

Of the 23 eight divisors of 792 256 larger than one, only [1, 4, 9, 22, 36, 88, 198, 79216, 64, 256] are in A340784. Using these factors gives , we obtain the following possible factorizations 792 : 256 = 64*4*198 = 916*88 16 = 2216*4*36 4 = 4*94*4*22, 4, therefore a(792256) = 5.

Of the 23 divisors of 792 larger than one, only [4, 9, 22, 36, 88, 198, 792] are in A340784. Using these factors gives the following possible factorizations: 792 = 198*4 = 88*9 = 36*22 = 22*4*9, therefore a(792) = 5.