The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A293774 (Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
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A293774

Number of permutations of length n sortable by 3 passes through a pop-stack.
(history; published version)

#17 by N. J. A. Sloane at Sat Oct 21 22:02:52 EDT 2017

STATUS

proposed

approved

#16 by Michel Marcus at Sat Oct 21 11:12:26 EDT 2017

STATUS

editing

proposed

#15 by Michel Marcus at Sat Oct 21 11:12:22 EDT 2017

LINKS

Bjarki Ágúst Guðmundsson, <a href="/A293774/b293774.txt">Table of n, a(n) for n = 0..1000</a>.

PROG

(PARI) Vec((2*x^10 + 4*x^9 + 2*x^8 + 5*x^7 + 11*x^6 + 8*x^5 + 6*x^4 + 6*x^3 + 2*x^2 + x - 1)/(4*x^10 + 8*x^9 + 4*x^8 + 10*x^7 + 22*x^6 + 16*x^5 + 8*x^4 + 6*x^3 + 2*x^2 + 2*x - 1) + O(x^30)) \\ _Bjarki Ágúst Guðmundsson_, Oct 16 2017

STATUS

proposed

editing

#14 by Bjarki Ágúst Guðmundsson at Sat Oct 21 10:56:21 EDT 2017

STATUS

editing

proposed

#13 by Bjarki Ágúst Guðmundsson at Sat Oct 21 10:55:10 EDT 2017

LINKS

Bjarki Ágúst Guðmundsson, <a href="/A293774/b293774.txt">Table of n, a(n) for n = 0..1000</a>.

STATUS

approved

editing

#12 by N. J. A. Sloane at Fri Oct 20 15:59:46 EDT 2017

STATUS

proposed

approved

#11 by Michel Marcus at Mon Oct 16 09:55:18 EDT 2017

STATUS

editing

proposed

#10 by Michel Marcus at Mon Oct 16 09:55:06 EDT 2017

FORMULA

G.f.: (2*x^10 + 4*x^9 + 2*x^8 + 5*x^7 + 11*x^6 + 8*x^5 + 6*x^4 + 6*x^3 + 2*x^2 + x - 1) / (4*x^10 + 8*x^9 + 4*x^8 + 10*x^7 + 22*x^6 + 16*x^5 + 8*x^4 + 6*x^3 + 2*x^2 + 2*x - 1).

CROSSREFS

Cf. A224232, A293775, A293776, A293784.

STATUS

proposed

editing

Discussion

Mon Oct 16

09:55

Michel Marcus: punctuation

#9 by Bjarki Ágúst Guðmundsson at Mon Oct 16 09:15:37 EDT 2017

STATUS

editing

proposed

#8 by Bjarki Ágúst Guðmundsson at Mon Oct 16 09:15:18 EDT 2017

CROSSREFS

Cf. A224232, A293775, A293776, A293784

STATUS

proposed

editing