The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A057030

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A057030

Let P(n) of a sequence s(1),s(2),s(3),... be obtained by leaving s(1),...,s(n-1) fixed and reversing every n consecutive terms thereafter; apply P(2) to 1,2,3,... to get PS(2), then apply P(3) to PS(2) to get PS(3), then apply P(4) to PS(3), etc. The limit of PS(n) is A057030.
(history; published version)

#19 by Peter Luschny at Wed Apr 24 07:52:41 EDT 2024

STATUS

reviewed

approved

#18 by Vaclav Kotesovec at Wed Apr 24 07:47:11 EDT 2024

STATUS

proposed

reviewed

#17 by Mikhail Kurkov at Wed Apr 24 07:45:47 EDT 2024

STATUS

editing

proposed

#16 by Mikhail Kurkov at Wed Apr 24 07:45:33 EDT 2024

FORMULA

Conjecture: a(n) = A007062(n+1) - 1 for n > 0. - Mikhail Kurkov, Mar 10 2022 [verification needed]

PROG

(PARI) a(n)=local(A=n, B); for(i=1, n-1, B=n-i; A=A+B-2*(A%B)); A \\ Mikhail Kurkov, Mar 10 2022 [verification needed]

STATUS

approved

editing

Discussion

Wed Apr 24

07:45

Mikhail Kurkov: Program is based on a conjecture.

#15 by Michael De Vlieger at Sun Apr 21 21:12:27 EDT 2024

STATUS

proposed

approved

#14 by Jon E. Schoenfield at Sun Apr 21 21:11:30 EDT 2024

STATUS

editing

proposed

#13 by Jon E. Schoenfield at Sun Apr 21 21:11:28 EDT 2024

FORMULA

a(n) = A007062(n+1) - 1 for n > 0. - Mikhail Kurkov, Mar 10 2022 [verification needed]

PROG

(PARI) a(n)=local(A=n, B); for(i=1, n-1, B=n-i; A=A+B-2*(A%B)); A \\ Mikhail Kurkov, Mar 10 2022 [verification needed]

STATUS

approved

editing

#12 by N. J. A. Sloane at Wed Apr 20 00:17:03 EDT 2022

STATUS

proposed

approved

#11 by Michel Marcus at Thu Mar 10 05:30:12 EST 2022

STATUS

editing

proposed

#10 by Michel Marcus at Thu Mar 10 05:30:10 EST 2022

EXAMPLE

PS(2) begins with 1,3,2,5,4,7,6; PS(3) with 1,3,4,5,2,9,6; PS(4) with 1,3,4,6,9,2,5,

PS(3) begins with 1,3,4,5,2,9,6;

PS(4) begins with 1,3,4,6,9,2,5.

STATUS

proposed

editing