cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

Showing 1-5 of 5 results.

A220172 Sum of neighbor maps: number of n X 1 binary arrays indicating the locations of corresponding elements equal to the sum mod 3 of their horizontal, vertical and antidiagonal neighbors in a random 0..2 n X 1 array.

Original entry on oeis.org

2, 2, 8, 16, 24, 64, 128, 232, 512, 1024, 1984, 4096, 8192, 16224, 32768, 65536, 130688, 262144, 524288, 1047680, 2097152, 4194304, 8386560, 16777216, 33554432, 67104256, 134217728, 268435456, 536860672, 1073741824, 2147483648, 4294944768
Offset: 1

Views

Author

R. H. Hardin, Dec 06 2012

Keywords

Comments

Column 1 of A220177.

Examples

			All solutions for n=3:
..1....0....1....1....0....0....0....1
..1....1....0....1....0....0....1....0
..0....0....1....1....0....1....1....0
		

Formula

Empirical: a(n) = 2*a(n-1) +4*a(n-3) -8*a(n-4) -4*a(n-6) +8*a(n-7).
Empirical g.f.: 2*(1 - x + 2*x^2 - 4*x^3 + 4*x^6) / ((1 - 2*x)*(1 - 2*x^3)^2). - Colin Barker, Feb 18 2018

A220173 Sum of neighbor maps: number of nX2 binary arrays indicating the locations of corresponding elements equal to the sum mod 3 of their horizontal, vertical and antidiagonal neighbors in a random 0..2 nX2 array.

Original entry on oeis.org

2, 16, 48, 256, 856, 4096, 15872, 65536, 259584, 1048576, 4177632, 16777216, 67051520, 268435456, 1073479680, 4294967296, 17178580480, 68719476736, 274872664064, 1099511627776, 4398023442432, 17592186044416, 70368641459200
Offset: 1

Views

Author

R. H. Hardin Dec 06 2012

Keywords

Comments

Column 2 of A220177

Examples

			Some solutions for n=3
..0..1....1..1....0..0....0..0....1..0....0..1....1..0....1..0....0..1....0..0
..1..0....0..0....1..1....0..0....1..1....1..0....0..1....1..1....1..1....1..1
..1..0....0..0....1..1....1..0....0..1....0..1....0..0....1..0....1..0....0..1
		

Formula

Empirical: a(n) = 4*a(n-1) +8*a(n-2) -32*a(n-3) -16*a(n-4) +64*a(n-5) +52*a(n-6) -208*a(n-7) -416*a(n-8) +1664*a(n-9) +832*a(n-10) -3328*a(n-11) -1056*a(n-12) +4224*a(n-13) +8448*a(n-14) -33792*a(n-15) -16896*a(n-16) +67584*a(n-17) +10880*a(n-18) -43520*a(n-19) -87040*a(n-20) +348160*a(n-21) +174080*a(n-22) -696320*a(n-23) -62720*a(n-24) +250880*a(n-25) +501760*a(n-26) -2007040*a(n-27) -1003520*a(n-28) +4014080*a(n-29) +205824*a(n-30) -823296*a(n-31) -1646592*a(n-32) +6586368*a(n-33) +3293184*a(n-34) -13172736*a(n-35) -360448*a(n-36) +1441792*a(n-37) +2883584*a(n-38) -11534336*a(n-39) -5767168*a(n-40) +23068672*a(n-41) +262144*a(n-42) -1048576*a(n-43) -2097152*a(n-44) +8388608*a(n-45) +4194304*a(n-46) -16777216*a(n-47)

A220174 Sum of neighbor maps: number of nX3 binary arrays indicating the locations of corresponding elements equal to the sum mod 3 of their horizontal, vertical and antidiagonal neighbors in a random 0..2 nX3 array.

Original entry on oeis.org

8, 48, 404, 4096, 31744, 262144, 2083808, 16728064, 134217728, 1073741824, 8586101128, 68719476736, 549755813888, 4397962625024, 35184307884032, 281474976710656, 2251796592459776, 18014398509481984, 144115183550922752
Offset: 1

Views

Author

R. H. Hardin Dec 06 2012

Keywords

Comments

Column 3 of A220177

Examples

			Some solutions for n=3
..0..1..0....1..0..1....1..0..0....0..0..0....0..0..0....0..0..1....1..0..0
..0..0..0....0..0..0....0..0..0....0..0..0....1..1..0....0..0..1....0..1..1
..1..1..1....0..0..0....0..1..1....1..1..1....0..1..1....0..0..0....1..1..1
		

A220175 Sum of neighbor maps: number of nX4 binary arrays indicating the locations of corresponding elements equal to the sum mod 3 of their horizontal, vertical and antidiagonal neighbors in a random 0..2 nX4 array.

Original entry on oeis.org

16, 256, 4096, 65536, 1048576, 16777216, 268435456, 4294967296, 68701991383
Offset: 1

Views

Author

R. H. Hardin Dec 06 2012

Keywords

Comments

Column 4 of A220177
a(n)=16^n for n<=8 but not for n=9

Examples

			Some solutions for n=3
..1..1..0..1....0..1..0..1....1..0..1..0....0..0..0..1....1..1..0..1
..1..1..0..0....0..1..0..0....1..1..0..1....0..1..0..0....0..0..1..1
..0..0..1..0....0..0..1..1....0..1..0..1....0..1..0..0....0..0..0..0
		

A220176 Sum of neighbor maps: number of nX5 binary arrays indicating the locations of corresponding elements equal to the sum mod 3 of their horizontal, vertical and antidiagonal neighbors in a random 0..2 nX5 array.

Original entry on oeis.org

24, 856, 31744, 1048576, 32395806, 1073741824, 34351349760
Offset: 1

Views

Author

R. H. Hardin Dec 06 2012

Keywords

Comments

Column 5 of A220177

Examples

			Some solutions for n=3
..1..0..0..0..0....1..0..0..0..1....0..1..0..0..1....0..1..1..1..0
..0..0..0..0..1....1..1..0..0..1....0..0..1..0..1....0..0..1..1..0
..0..1..1..1..1....0..0..1..1..0....0..1..0..0..1....0..1..1..0..0
		
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