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Revision History for A220227 (Underlined text is an addition; strikethrough text is a deletion.)

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A220227 Majority value maps: number of 2 X n binary arrays indicating the locations of corresponding elements equal to at least half of their horizontal, diagonal and antidiagonal neighbors in a random 0..1 2 X n array.
(history; published version)
#7 by Susanna Cuyler at Tue Jul 31 07:22:43 EDT 2018
STATUS

proposed

approved

#6 by Colin Barker at Tue Jul 31 06:57:10 EDT 2018
STATUS

editing

proposed

#5 by Colin Barker at Tue Jul 31 06:56:44 EDT 2018
NAME

Majority value maps: number of 2 X 2Xnn binary arrays indicating the locations of corresponding elements equal to at least half of their horizontal, diagonal and antidiagonal neighbors in a random 0..1 2 X 2Xnn array.

COMMENTS

Row 2 of A220226.

FORMULA

Empirical: a(n) = 2*a(n-1) +) + a(n-2) +) + 6*a(n-3) +) + a(n-4) +) + 3*a(n-5) -) - 4*a(n-6) -) - 2*a(n-7) -) - 4*a(n-8)).

Empirical g.f.: x*(1 - x)*(1 + 2*x)^2*(1 + x^2)*(1 + x + x^2) / (1 - 2*x - x^2 - 6*x^3 - x^4 - 3*x^5 + 4*x^6 + 2*x^7 + 4*x^8). - Colin Barker, Jul 31 2018

EXAMPLE

Some solutions for n=3:

CROSSREFS

Cf. A220226.

STATUS

approved

editing

#4 by R. H. Hardin at Sat Dec 08 04:51:22 EST 2012
STATUS

editing

approved

#3 by R. H. Hardin at Sat Dec 08 04:51:12 EST 2012
LINKS

R. H. Hardin, <a href="/A220227/b220227.txt">Table of n, a(n) for n = 1..210</a>

#2 by R. H. Hardin at Sat Dec 08 04:50:59 EST 2012
NAME

allocated for R. H. Hardin

Majority value maps: number of 2Xn binary arrays indicating the locations of corresponding elements equal to at least half of their horizontal, diagonal and antidiagonal neighbors in a random 0..1 2Xn array

DATA

1, 6, 18, 51, 157, 477, 1445, 4384, 13297, 40332, 122339, 371085, 1125588, 3414184, 10356065, 31412486, 95281776, 289013030, 876647491, 2659087097, 8065664119, 24465139829, 74208776604, 225093441705, 682763681270, 2070989900565

OFFSET

1,2

COMMENTS

Row 2 of A220226

FORMULA

Empirical: a(n) = 2*a(n-1) +a(n-2) +6*a(n-3) +a(n-4) +3*a(n-5) -4*a(n-6) -2*a(n-7) -4*a(n-8)

EXAMPLE

Some solutions for n=3

..1..1..0....1..1..1....1..0..0....1..0..1....0..1..0....0..1..1....1..1..1

..1..1..0....1..0..1....0..0..0....1..1..1....1..1..1....0..1..1....0..1..0

KEYWORD

allocated

nonn

AUTHOR

R. H. Hardin Dec 08 2012

STATUS

approved

editing

#1 by R. H. Hardin at Sat Dec 08 04:44:37 EST 2012
NAME

allocated for R. H. Hardin

KEYWORD

allocated

STATUS

approved

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Last modified August 29 18:55 EDT 2024. Contains 375518 sequences. (Running on oeis4.)