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Revision History for A122141

(Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
Showing entries 1-10 | older changes

Array: T(d,n) = number of ways of writing n as a sum of d squares, read by ascending antidiagonals.
(history; published version)

#56 by Michael De Vlieger at Tue Feb 13 08:16:18 EST 2024

STATUS

reviewed

approved

#55 by Kevin Ryde at Tue Feb 13 01:31:47 EST 2024

STATUS

proposed

reviewed

#54 by Michel Marcus at Thu Feb 08 11:17:20 EST 2024

STATUS

editing

proposed

Discussion

Thu Feb 08

11:17

Michel Marcus: Heiz was not ok; so I think better remove

11:22

Darío Clavijo: It's ok

11:26

Darío Clavijo: I though due attribution was in order...

Fri Feb 09

19:39

Jon E. Schoenfield: Sometimes it is, if the name is spelled correctly ...  ;-)

21:22

Darío Clavijo: I'm sorry, my bad...

#53 by Michel Marcus at Thu Feb 08 11:16:35 EST 2024

PROG

# Code after Alois P. Heiz.

STATUS

proposed

editing

#52 by Kevin Ryde at Wed Feb 07 21:02:02 EST 2024

STATUS

editing

proposed

#51 by Kevin Ryde at Wed Feb 07 21:00:43 EST 2024

PROG

def aT(d, n):

return aT(d-1, n) + sum(aT(d-1, n-(j**2)) for j in range(1, isqrt(n)+1)) * 2 # Darío Clavijo, Feb 06 2024

STATUS

proposed

editing

Discussion

Wed Feb 07

21:02

Kevin Ryde: When using sympy, is its diophantine.py sum_of_squares() any good?  Looks like unordered and without signs, so some further crunching to apply.

#50 by Jon E. Schoenfield at Tue Feb 06 19:02:43 EST 2024

STATUS

editing

proposed

#49 by Jon E. Schoenfield at Tue Feb 06 19:02:14 EST 2024

EXAMPLE

Array T(d,n) with rows d = 1,2,3,... and columns n = 0,1,2,3,... reads

1 2 0 0 2 0 0 0 0 2 0 ...

1 4 4 0 4 8 0 0 4 4 8 ...

1 6 12 8 6 24 24 0 12 30 24 ...

1 8 24 32 24 48 96 64 24 104 144 ...

1 10 40 80 90 112 240 320 200 250 560 ...

1 12 60 160 252 312 544 960 1020 876 1560 ...

1 14 84 280 574 840 1288 2368 3444 3542 4424 ...

1 16 112 448 1136 2016 3136 5504 9328 12112 14112 ...

1 18 144 672 2034 4320 7392 12672 22608 34802 44640 ...

1 20 180 960 3380 8424 16320 28800 52020 88660 129064 ...

STATUS

proposed

editing

#48 by Michel Marcus at Tue Feb 06 17:06:40 EST 2024

STATUS

editing

proposed

#47 by Michel Marcus at Tue Feb 06 17:05:40 EST 2024

EXAMPLE

1 2 0 0 2 0 0 0 0 2 0 ...

1 4 4 0 4 8 0 0 4 4 8 ...

1 6 12 8 6 24 24 0 12 30 24 ...

1 8 24 32 24 48 96 64 24 104 144 ...

1 10 40 80 90 112 240 320 200 250 560 ...

1 12 60 160 252 312 544 960 1020 876 1560 ...

1 14 84 280 574 840 1288 2368 3444 3542 4424 ...

1 16 112 448 1136 2016 3136 5504 9328 12112 14112 ...

1 18 144 672 2034 4320 7392 12672 22608 34802 44640 ...

1 20 180 960 3380 8424 16320 28800 52020 88660 129064

STATUS

proposed

editing