The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A229607

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A229607

Square array read by antidiagonals downwards in which each row starts with the least prime not in a previous row, and each prime p in a row is followed by the greatest prime < 2*p.
(history; published version)

#31 by OEIS Server at Mon Jan 20 22:53:41 EST 2025

LINKS

Pontus von Brömssen, <a href="/A229607/b229607_1.txt">Table of n, a(n) for n = 1..5050</a> (first 100 antidiagonals)

#30 by N. J. A. Sloane at Mon Jan 20 22:53:41 EST 2025

STATUS

proposed

approved

Discussion

Mon Jan 20

22:53

OEIS Server: Installed first b-file as b229607.txt.

#29 by Omar E. Pol at Sun Jan 19 12:08:20 EST 2025

STATUS

editing

proposed

#28 by Omar E. Pol at Sun Jan 19 12:08:17 EST 2025

NAME

Square array read by antidiagonals downwards: in which each row starts with the least prime not in a previous row, and each prime p in a row is followed by the greatest prime < 2*p.

#27 by Omar E. Pol at Sun Jan 19 12:07:27 EST 2025

NAME

ArraySquare array read by antidiagonals downwards: each row starts with the least prime not in a previous row, and each prime p in a row is followed by the greatest prime < 2*p.

STATUS

proposed

editing

#26 by Pontus von Brömssen at Sun Jan 19 11:23:02 EST 2025

STATUS

editing

proposed

#25 by Pontus von Brömssen at Sat Jan 18 12:45:12 EST 2025

COMMENTS

- Column 1 is A164368, not A104272. It seems that the first column would be A104272 if no duplicates were allowed, i.e., if the prime p in a row were followed by the largest prime < 2*p not in a previous row; see A380277.

CROSSREFS

Cf. A006992, A104272, A164368, A229608, A229609, A229610, A380277.

Discussion

Sat Jan 18

12:48

Pontus von Brömssen: Considering that a comment in the original submission said "Every prime occurs exactly once", maybe A380277 is what the author intended here.

#24 by Pontus von Brömssen at Sat Jan 18 10:37:04 EST 2025

LINKS

Pontus von Brömssen, <a href="/A229607/b229607_1.txt">Table of n, a(n) for n = 1..5050</a> (first 100 antidiagonals)

Discussion

Sat Jan 18

10:38

Pontus von Brömssen: I'm working on a submission of the version of this array without duplicates mentioned in my comment.

#23 by Pontus von Brömssen at Sat Jan 18 10:19:59 EST 2025

COMMENTS

From Pontus von Brömssen, Jan 17 18 2025: (Start)

- Column 1 is A164368, not A104272.

STATUS

approved

editing

#22 by Michel Marcus at Fri Jan 17 08:47:22 EST 2025

STATUS

reviewed

approved