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A220283 Equals one maps: number of nX2 binary arrays indicating the locations of corresponding elements equal to exactly one of their horizontal and vertical neighbors in a random 0..1 nX2 array 2
2, 4, 31, 96, 424, 1422, 5504, 19606, 73294, 266630, 985354, 3607564, 13279027, 48721400, 179090319, 657572014, 2415928734, 8872778822, 32593085529, 119711114434, 439717298204, 1615076013180, 5932289053689, 21789374848574 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 2 of A220287

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..210

FORMULA

Empirical: a(n) = 11*a(n-1) -38*a(n-2) +3*a(n-3) +273*a(n-4) -585*a(n-5) +163*a(n-6) +1138*a(n-7) -2783*a(n-8) +4248*a(n-9) -1873*a(n-10) -9106*a(n-11) +20882*a(n-12) -16423*a(n-13) -2894*a(n-14) +29328*a(n-15) -64667*a(n-16) +57077*a(n-17) +7835*a(n-18) +33002*a(n-19) -214480*a(n-20) +380503*a(n-21) -473048*a(n-22) -7236*a(n-23) +1761437*a(n-24) -4294641*a(n-25) +6923832*a(n-26) -9655487*a(n-27) +11841807*a(n-28) -14350503*a(n-29) +20243605*a(n-30) -30073838*a(n-31) +42142135*a(n-32) -53997680*a(n-33) +59808207*a(n-34) -56918978*a(n-35) +49815419*a(n-36) -44280580*a(n-37) +45956243*a(n-38) -59728794*a(n-39) +73013849*a(n-40) -75824776*a(n-41) +59437004*a(n-42) -24886315*a(n-43) -13755017*a(n-44) +37112277*a(n-45) -38824998*a(n-46) +24036641*a(n-47) +1556561*a(n-48) -13532613*a(n-49) +16676591*a(n-50) -8351532*a(n-51) -1444994*a(n-52) +8304511*a(n-53) -8619173*a(n-54) +5663049*a(n-55) -3195347*a(n-56) -2177828*a(n-57) +1197405*a(n-58) -3015864*a(n-59) +1195200*a(n-60) +168657*a(n-61) +60704*a(n-62) +1196966*a(n-63) -67458*a(n-64) +278858*a(n-65) +108811*a(n-66) -170807*a(n-67) +23752*a(n-68) -119899*a(n-69) -45780*a(n-70) -13842*a(n-71) -32740*a(n-72) +5874*a(n-73) +4752*a(n-74) +5808*a(n-75) +5816*a(n-76) +684*a(n-77) +984*a(n-78) +468*a(n-79) -40*a(n-80) -64*a(n-81) -240*a(n-82) -96*a(n-83)

EXAMPLE

Some solutions for n=3

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

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

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

CROSSREFS

Sequence in context: A334488 A296249 A181620 * A339603 A188113 A259115

Adjacent sequences:  A220280 A220281 A220282 * A220284 A220285 A220286

KEYWORD

nonn

AUTHOR

R. H. Hardin Dec 09 2012

STATUS

approved

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Last modified May 24 04:25 EDT 2022. Contains 354005 sequences. (Running on oeis4.)