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 1-10 of 13 results. Next

A218663 T(n,k) = Hilltop maps: number of n X k binary arrays indicating the locations of corresponding elements not exceeded by any king-move neighbor in a random 0..1 n X k array.

Original entry on oeis.org

1, 3, 3, 5, 15, 5, 9, 57, 57, 9, 17, 225, 417, 225, 17, 31, 891, 3249, 3249, 891, 31, 57, 3519, 25533, 50625, 25533, 3519, 57, 105, 13905, 199489, 793881, 793881, 199489, 13905, 105, 193, 54945, 1560161, 12383361, 24879489, 12383361, 1560161, 54945
Offset: 1

Views

Author

R. H. Hardin, Nov 04 2012

Keywords

Comments

From Andrew Howroyd, May 10 2017: (Start)
Number of n X k binary matrices with every 1 adjacent to some 0 horizontally, vertically, diagonally or antidiagonally.
Number of dominating sets in the n X k king graph. (End)

Examples

			Table starts
....1........3...........5...............9.................17
....3.......15..........57.............225................891
....5.......57.........417............3249..............25533
....9......225........3249...........50625.............793881
...17......891.......25533..........793881...........24879489
...31.....3519......199489........12383361..........775176415
...57....13905.....1560161.......193349025........24176619049
..105....54945....12202673......3018953025.......754066017977
..193...217107....95434773.....47135449449.....23517838102321
..355...857871...746388537....735942652641....733484062428443
..653..3389769..5837454753..11490533873361..22876204302519509
.1201.13394241.45654295713.179405691966081.713472099034206097
...
Some solutions for n=3 k=4
..1..1..1..0....1..0..1..1....0..1..0..1....0..1..1..0....1..0..0..0
..0..1..0..0....0..0..0..0....1..0..0..1....0..0..1..1....0..0..1..1
..0..1..0..1....1..1..0..1....0..1..1..1....1..1..0..1....1..1..0..0
		

Crossrefs

Columns 1-7 are A000213(n+1), A218657, A218658, A218659, A218660, A218661, A218662.
Diagonal is A133791.

Formula

Empirical for column k:
k=1: a(n) = a(n-1) +a(n-2) +a(n-3)
k=2: a(n) = 3*a(n-1) +3*a(n-2) +3*a(n-3)
k=3: a(n) = 6*a(n-1) +11*a(n-2) +26*a(n-3) -5*a(n-4) -5*a(n-6)
k=4: a(n) = 12*a(n-1) +45*a(n-2) +180*a(n-3) -27*a(n-4) -81*a(n-6)
Columns k=1..z+1 for an underlying 0..z array: a(n) = sum(i=1..2z+1){(2^k-1)*a(n-i)} checked for z=1..3.

A219079 Hilltop maps: number of 2Xn binary arrays indicating the locations of corresponding elements not exceeded by any horizontal, diagonal or antidiagonal neighbor in a random 0..1 2Xn array.

Original entry on oeis.org

1, 11, 47, 165, 625, 2435, 9367, 35901, 137865, 529675, 2034399, 7813333, 30009313, 115260115, 442689383, 1700273453, 6530386425, 25081819099, 96333894191, 369997847365, 1421082488529, 5458073486883, 20963291245879, 80515511728413
Offset: 1

Views

Author

R. H. Hardin Nov 11 2012

Keywords

Comments

Row 2 of A219078

Examples

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

Formula

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

A219073 Hilltop maps: number of n X 3 binary arrays indicating the locations of corresponding elements not exceeded by any horizontal, diagonal or antidiagonal neighbor in a random 0..1 n X 3 array.

Original entry on oeis.org

5, 47, 337, 2469, 18499, 137251, 1019123, 7573641, 56263253, 417979331, 3105269893, 23069495037, 171386678155, 1273258576351, 9459233511263, 70274099126769, 522077106920261, 3878591175268919, 28814650755208777
Offset: 1

Views

Author

R. H. Hardin, Nov 11 2012

Keywords

Comments

Column 3 of A219078.

Examples

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

Crossrefs

Cf. A219078.

Formula

Empirical: a(n) = 5*a(n-1) + 11*a(n-2) + 51*a(n-3) + 7*a(n-4) + 27*a(n-5) - 33*a(n-6) - 3*a(n-7).
Empirical g.f.: x*(5 + 22*x + 47*x^2 + 12*x^3 + 15*x^4 - 54*x^5 - 3*x^6) / (1 - 5*x - 11*x^2 - 51*x^3 - 7*x^4 - 27*x^5 + 33*x^6 + 3*x^7). - Colin Barker, Jul 25 2018

A219074 Hilltop maps: number of nX4 binary arrays indicating the locations of corresponding elements not exceeded by any horizontal, diagonal or antidiagonal neighbor in a random 0..1 nX4 array.

Original entry on oeis.org

9, 165, 2321, 32945, 477309, 6879341, 99118753, 1428782305, 20594013941, 296830835781, 4278398369137, 61667023808785, 888841954030797, 12811387949686973, 184657868037699425, 2661579521073401057
Offset: 1

Views

Author

R. H. Hardin Nov 11 2012

Keywords

Comments

Column 4 of A219078

Examples

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

Formula

Empirical: a(n) = 11*a(n-1) +33*a(n-2) +233*a(n-3) +13*a(n-4) -31*a(n-5) -657*a(n-6) -321*a(n-7) -288*a(n-8) -64*a(n-9) +64*a(n-10)

A219075 Hilltop maps: number of nX5 binary arrays indicating the locations of corresponding elements not exceeded by any horizontal, diagonal or antidiagonal neighbor in a random 0..1 nX5 array.

Original entry on oeis.org

17, 625, 17537, 494713, 14228041, 407374825, 11660290321, 333882416305, 9559854123673, 273717397488937, 7837125931615553, 224393896465841065, 6424880595963477921, 183958193843792111121, 5267120030903659835073
Offset: 1

Views

Author

R. H. Hardin Nov 11 2012

Keywords

Comments

Column 5 of A219078

Examples

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

Formula

Empirical: a(n) = 20*a(n-1) +158*a(n-2) +2330*a(n-3) +5837*a(n-4) +17850*a(n-5) -57426*a(n-6) -279582*a(n-7) -163347*a(n-8) +746554*a(n-9) +983888*a(n-10) -474072*a(n-11) -1651489*a(n-12) -646204*a(n-13) +913420*a(n-14) +1038852*a(n-15) +300209*a(n-16) -257176*a(n-17) -347922*a(n-18) -148694*a(n-19) +11843*a(n-20) -2590*a(n-21) +19366*a(n-22) -18694*a(n-23) +8067*a(n-24) -1302*a(n-25) -60*a(n-26) +180*a(n-27) -15*a(n-28)

A219076 Hilltop maps: number of nX6 binary arrays indicating the locations of corresponding elements not exceeded by any horizontal, diagonal or antidiagonal neighbor in a random 0..1 nX6 array.

Original entry on oeis.org

31, 2435, 134809, 7561349, 433704331, 24734141495, 1410242020653, 80444813963129, 4588436794733591, 261712432286491659, 14927540586501299193, 851435525780779197693, 48564066186463152044491, 2769991245247350703909311
Offset: 1

Views

Author

R. H. Hardin Nov 11 2012

Keywords

Comments

Column 6 of A219078

Examples

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

A219077 Hilltop maps: number of nX7 binary arrays indicating the locations of corresponding elements not exceeded by any horizontal, diagonal or antidiagonal neighbor in a random 0..1 nX7 array.

Original entry on oeis.org

57, 9367, 1023441, 113959413, 12998933707, 1473655240387, 167024618548071, 18939932662217929, 2147519964457580465, 243494396494378271955, 27608646901560676777421, 3130407281278669890215213
Offset: 1

Views

Author

R. H. Hardin Nov 11 2012

Keywords

Comments

Column 7 of A219078

Examples

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

A219080 Hilltop maps: number of 3 X n binary arrays indicating the locations of corresponding elements not exceeded by any horizontal, diagonal or antidiagonal neighbor in a random 0..1 3 X n array.

Original entry on oeis.org

1, 41, 337, 2321, 17537, 134809, 1023441, 7759553, 58921537, 447447561, 3397273553, 25794057969, 195847550081, 1487017265657, 11290490704977, 85725445999521, 650888811968321, 4942012485147241, 37523285458920273
Offset: 1

Views

Author

R. H. Hardin, Nov 11 2012

Keywords

Comments

Row 3 of A219078.

Examples

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

Crossrefs

Cf. A219078.

Formula

Empirical: a(n) = 6*a(n-1) + 5*a(n-2) + 46*a(n-3) + 61*a(n-4) - 10*a(n-5) - a(n-6) - 10*a(n-7).
Empirical g.f.: x*(1 + 35*x + 86*x^2 + 48*x^3 - 21*x^4 - 11*x^5 - 10*x^6) / (1 - 6*x - 5*x^2 - 46*x^3 - 61*x^4 + 10*x^5 + x^6 + 10*x^7). - Colin Barker, Jul 25 2018

A219081 Hilltop maps: number of 4Xn binary arrays indicating the locations of corresponding elements not exceeded by any horizontal, diagonal or antidiagonal neighbor in a random 0..1 4Xn array.

Original entry on oeis.org

1, 149, 2469, 32945, 494713, 7561349, 113959413, 1715622809, 25868247057, 390055483301, 5880485889397, 88654851159857, 1336593648057193, 20150953522466741, 303802286301958197, 4580222640012373465
Offset: 1

Views

Author

R. H. Hardin Nov 11 2012

Keywords

Comments

Row 4 of A219078

Examples

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

Formula

Empirical: a(n) = 10*a(n-1) +44*a(n-2) +384*a(n-3) +1502*a(n-4) +1612*a(n-5) -478*a(n-6) -4742*a(n-7) -13053*a(n-8) -13178*a(n-9) -7218*a(n-10) -8982*a(n-11) -108*a(n-12) +3888*a(n-13)

A219082 Hilltop maps: number of 5Xn binary arrays indicating the locations of corresponding elements not exceeded by any horizontal, diagonal or antidiagonal neighbor in a random 0..1 5Xn array.

Original entry on oeis.org

1, 547, 18499, 477309, 14228041, 433704331, 12998933707, 389034040749, 11664778284009, 349775255769979, 10486116624897067, 314370999692984261, 9424956803519213353, 282563157923689218059, 8471313961048080841195
Offset: 1

Views

Author

R. H. Hardin Nov 11 2012

Keywords

Comments

Row 5 of A219078

Examples

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

Formula

Empirical: a(n) = 20*a(n-1) +146*a(n-2) +3532*a(n-3) +27431*a(n-4) +116656*a(n-5) +474493*a(n-6) -504690*a(n-7) -9727761*a(n-8) -24028992*a(n-9) -66423882*a(n-10) -41186382*a(n-11) +707203710*a(n-12) +1057707036*a(n-13) +400102378*a(n-14) +2214831924*a(n-15) -8080578503*a(n-16) -15125172488*a(n-17) +2822970974*a(n-18) -20788048752*a(n-19) +25829191223*a(n-20) +56646466196*a(n-21) -24732078735*a(n-22) +59826555806*a(n-23) -56845699775*a(n-24) -45194311324*a(n-25) +8339540130*a(n-26) -13101220366*a(n-27) +23960611452*a(n-28) +18278792048*a(n-29) -10927311264*a(n-30) -3516015456*a(n-31) +2062115264*a(n-32) -872547840*a(n-33) -203788800*a(n-34) +235008000*a(n-35)
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