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Revision History for A224701 (Bold, blue-underlined text is an addition; faded, red-underlined text is a deletion.)

Showing entries 1-10 | older changes
Table read by antidiagonals of numbers of form (2^n - 1)*2^(m+3) + 5 where n>=1, m>=1.
(history; published version)
#14 by Charles R Greathouse IV at Thu Sep 08 08:46:04 EDT 2022
PROG

(MAGMAMagma)

Discussion
Thu Sep 08
08:46
OEIS Server: https://oeis.org/edit/global/2944
#13 by Jon E. Schoenfield at Fri Jun 23 03:55:09 EDT 2017
STATUS

editing

approved

#12 by Jon E. Schoenfield at Fri Jun 23 03:55:05 EDT 2017
NAME

Table read by antidiagonals of numbers of form (2^n - 1)*2^(m+3) + 5 where n>=1, m>=1.

PROG

//along anti-diagonals antidiagonals from top. Primes in the sequence are marked with *.

STATUS

approved

editing

#11 by N. J. A. Sloane at Sat Dec 10 22:37:15 EST 2016
STATUS

proposed

approved

#10 by Jon E. Schoenfield at Sat Dec 10 17:42:11 EST 2016
STATUS

editing

proposed

#9 by Jon E. Schoenfield at Sat Dec 10 17:41:41 EST 2016
NAME

Table read by anti-diagonals antidiagonals of numbers of form (2^n -1)*2^(m+3) + 5 where n>=1, m>=1.

COMMENTS

The table has row labels 2^n - 1 and column labels 2^(m+3). The table entry is row*col + 5. A MAGMA program is provided that generates the numbers in a table format. The sequence is read along the anti-diagonals antidiagonals starting from the top left corner. Using the lexicographic ordering of A057555 the sequence is:

All of these numbers have the following property: let m be a member of A(n); if a sequence B(n) = all i such that i XOR (m - 1) = i - (m - 1), then the differences between successive members of B(n) is a repeating series

let of 1,1,1,5 ending with 1,1,1 and the last difference in the pattern m be a member . The total number of A1's and 5's in the pattern is 2^(nj+2), - 1, where j is the column index.

if a As an example, consider A(1), which is 21; the sequence B(n) = all i such that where i XOR (m - 1) 20 = i - (m - 20 starts as 20, 21, 22, 23, 28, 29, 30, 31, 52, ... with successive differences of 1, 1, 1, 5, 1, 1, 1), then, 21.

for A(2), which is 37, the sequence B(n) where i XOR 36 = i - 36 starts as 36, 37, 38, 39, 44, 45, 46, 47, 52, 53, 54, 55, 60, 61, 62, 63, 100, ... with successive differences between successive members of B(n) is a repeating series1, 1, 1, 5, 1, 1, 1, 5, 1, 1, 1, 5, 1, 1, 1, 37.

of 1,1,1,5 ending with 1,1,1 and the last difference in the pattern m.

The total number of 1's and 5's in the pattern is 2^(j+2) - 1, where

j is the column index.

As an example consider A(1) which is 21,

the sequence B(n) where i XOR 20 = i - 20 starts as:

20, 21, 22, 23, 28, 29, 30, 31, 52, ...

with successive differences of:

1, 1, 1, 5, 1, 1, 1, 21.

for A(2) which is 37,

the sequence B(n) where i XOR 36 = i - 36 starts as:

36, 37, 38, 39, 44, 45, 46, 47, 52, 53, 54, 55, 60, 61, 62, 63, 100,...

with successive differences of:

1, 1, 1, 5, 1, 1, 1, 5, 1, 1, 1, 5, 1, 1, 1, 37

CROSSREFS

Cf. A057555 (lexicographic ordering).

Rows : A168614(i=1) , n>=4.

Cols. : A220087(j=2) , n>=6.

STATUS

approved

editing

#8 by T. D. Noe at Fri May 03 14:36:05 EDT 2013
STATUS

editing

approved

#7 by T. D. Noe at Fri May 03 14:36:00 EDT 2013
LINKS

Brad Clardy, <a href="/A224701/b224701.txt">Table of n, a(n) for n = 1..9991000</a>

STATUS

proposed

editing

#6 by Brad Clardy at Thu May 02 07:12:12 EDT 2013
STATUS

editing

proposed

#5 by Brad Clardy at Thu May 02 07:03:34 EDT 2013
COMMENTS

The table has row labels 2^n - 1 and column labels 2^(m+3). The table entry is row*col + 5. A MAGMA program is provided that generates the numbers in a table format. The sequence is read along the anti-diagonals starting from the top left corner. Using the lexicographic ordering of A057555 the sequence is:

A(n) = Table(i,j) with (i,j)=(1,1),(1,2),(2,1),(1,3),(2,2),(3,1)...

let m be a member of A(n),

if a sequence B(n) = all i such that i XOR (m - 1) = i - (m - 1), then

the differences between successive members of B(n) is a repeating series

of 1,1,1,5 ending with 1,1,1 and the last difference in the pattern m.

The total number of 1's and 5's in the pattern is 2^(j+2) - 1, where

j is the column index.

FORMULA

a(n) = 2^(A057555(2*n - 1))*2^(A057555(2*n) + 3) + 5 for n>=1.

CROSSREFS

Cf. A057555(lexicographic ordering)

Discussion
Thu May 02
07:11
Brad Clardy: Two examples of the B(n) sequences were included for illustration purposes but neither of these is in OEIS. There is one more similar table sequence I would like to add and then that is it.