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.

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A228279 Number of n X 4 binary arrays with top left value 1 and no two ones adjacent horizontally, vertically or nw-se diagonally.

Original entry on oeis.org

3, 6, 35, 133, 587, 2448, 10414, 44024, 186414, 789100, 3340345, 14140347, 59858152, 253389483, 1072638232, 4540650778, 19221306410, 81366888278, 344439152622, 1458066449898, 6172230293325, 26128045670722, 110604228640954
Offset: 1

Views

Author

R. H. Hardin, Aug 19 2013

Keywords

Comments

Column 4 of A228285.

Examples

			Some solutions for n=4:
..1..0..1..0....1..0..0..1....1..0..0..1....1..0..1..0....1..0..0..0
..0..0..0..0....0..0..0..0....0..0..1..0....0..0..0..0....0..0..0..1
..1..0..1..0....0..0..0..0....0..0..0..0....0..0..1..0....0..1..0..0
..0..0..0..0....0..0..1..0....1..0..0..1....1..0..0..0....0..0..0..0
		

Crossrefs

See A228277-A228285, especially the latter.

Formula

a(n) = a(n-1) + 10*a(n-2) + 15*a(n-3) + 4*a(n-4) - 6*a(n-5) - a(n-6) + 3*a(n-7) - a(n-8).
G.f.: x*(1 - x)*(3 + 6*x + 5*x^2 - 2*x^3) / (1 - x - 10*x^2 - 15*x^3 - 4*x^4 + 6*x^5 + x^6 - 3*x^7 + x^8). - Colin Barker, Mar 16 2018

Extensions

Edited by N. J. A. Sloane, Aug 22 2013

A228280 Number of nX5 binary arrays with top left value 1 and no two ones adjacent horizontally, vertically or nw-se diagonally.

Original entry on oeis.org

5, 13, 112, 587, 3631, 21166, 126119, 745178, 4416695, 26150120, 154877307, 917205757, 5431915952, 32169045631, 190512481196, 1128258633821, 6681806858103, 39571194265886, 234349700556332, 1387872742075595
Offset: 1

Views

Author

R. H. Hardin Aug 19 2013

Keywords

Comments

Column 5 of A228285.

Examples

			Some solutions for n=4
..1..0..1..0..0....1..0..0..0..0....1..0..1..0..0....1..0..0..0..0
..0..0..0..0..0....0..0..0..1..0....0..0..0..0..0....0..0..0..0..1
..0..0..0..1..0....0..0..0..0..0....0..1..0..1..0....0..1..0..1..0
..0..1..0..0..0....0..0..1..0..1....1..0..0..0..0....1..0..0..0..0
		

Crossrefs

See A228277-A228285, especially the latter.
See also the k=5 variants of A228390, A228476, A228506 etc.

Formula

a(n) = a(n-1) +21*a(n-2) +48*a(n-3) +14*a(n-4) -69*a(n-5) -38*a(n-6) +68*a(n-7) +13*a(n-8) -57*a(n-9) +37*a(n-10) -8*a(n-11) -2*a(n-12) +a(n-13)
G.f.: x*(5 + 8*x - 6*x^2 - 38*x^3 - 2*x^4 - 5*x^5 + 45*x^6 - 51*x^7 + 26*x^8 - 4*x^9 - 2*x^10 + x^11)/((1 + 2*x - 2*x^3 + x^4)*(1 - 3*x - 15*x^2 - 16*x^3 + 11*x^4 + 20*x^5 - 19*x^6 + 8*x^7 - x^9)). - M. F. Hasler, Apr 27 2014

Extensions

Edited by N. J. A. Sloane, Aug 22 2013

A228281 Number of nX6 binary arrays with top left value 1 and no two ones adjacent horizontally, vertically or nw-se diagonally.

Original entry on oeis.org

8, 28, 337, 2448, 21166, 172082, 1428523, 11771298, 97268701, 802886174, 6629901197, 54739811878, 451976078779, 3731849749697, 30812948919061, 254414847888742, 2100639733295629, 17344457600010491, 143208852222784259
Offset: 1

Views

Author

R. H. Hardin Aug 19 2013

Keywords

Comments

Column 6 of A228285

Examples

			Some solutions for n=4
..1..0..0..0..0..0....1..0..0..0..1..0....1..0..0..0..1..0....1..0..1..0..0..1
..0..0..0..1..0..0....0..0..0..0..0..0....0..0..0..0..0..0....0..0..0..0..0..0
..0..1..0..0..0..1....0..0..0..0..0..0....0..0..1..0..0..1....0..0..0..0..0..0
..0..0..0..0..1..0....0..0..0..1..0..1....0..0..0..0..0..0....0..0..0..1..0..0
		

Crossrefs

See A228277-A228285, especially the latter.

Formula

a(n) = a(n-1) +42*a(n-2) +147*a(n-3) +70*a(n-4) -478*a(n-5) -449*a(n-6) +1199*a(n-7) +732*a(n-8) -2727*a(n-9) +659*a(n-10) +3827*a(n-11) -5776*a(n-12) +3926*a(n-13) -1152*a(n-14) -148*a(n-15) +154*a(n-16) +32*a(n-17) -29*a(n-18) -6*a(n-19) +3*a(n-20) +a(n-21)

Extensions

Edited by N. J. A. Sloane, Aug 22 2013

A228282 Number of nX7 binary arrays with top left value 1 and no two ones adjacent horizontally, vertically or nw-se diagonally.

Original entry on oeis.org

13, 60, 1034, 10414, 126119, 1428523, 16566199, 190540884, 2197847780, 25325358687, 291935092921, 3364727410265, 38782728207101, 447011297075966, 5152298718205939, 59385855860517581, 684486816741728022
Offset: 1

Views

Author

R. H. Hardin Aug 19 2013

Keywords

Comments

Column 7 of A228285

Examples

			Some solutions for n=4
..1..0..1..0..1..0..1....1..0..1..0..1..0..1....1..0..0..0..0..0..0
..0..0..0..0..0..0..0....0..0..0..0..0..0..0....0..0..0..0..0..0..0
..0..0..0..0..0..0..1....0..0..0..0..0..0..1....0..0..1..0..1..0..1
..0..0..1..0..0..0..0....1..0..1..0..1..0..0....0..1..0..0..0..0..0
		

Crossrefs

See A228277-A228285, especially the latter.

Formula

a(n) = a(n-1) +85*a(n-2) +432*a(n-3) +192*a(n-4) -3711*a(n-5) -5096*a(n-6) +21164*a(n-7) +27340*a(n-8) -112654*a(n-9) -37244*a(n-10) +477721*a(n-11) -464722*a(n-12) -897815*a(n-13) +3102284*a(n-14) -4149918*a(n-15) +2761082*a(n-16) -138325*a(n-17) -1353257*a(n-18) +942033*a(n-19) +64683*a(n-20) -365483*a(n-21) +80904*a(n-22) +92350*a(n-23) -27097*a(n-24) -23292*a(n-25) +2585*a(n-26) +5635*a(n-27) +1405*a(n-28) -561*a(n-29) -545*a(n-30) -173*a(n-31) -14*a(n-32) +5*a(n-33) +a(n-34)

Extensions

Edited by N. J. A. Sloane, Aug 22 2013

A228283 Number of nX8 binary arrays with top left value 1 and no two ones adjacent horizontally, vertically or nw-se diagonally.

Original entry on oeis.org

21, 129, 3154, 44024, 745178, 11771298, 190540884, 3057290265, 49208639399, 791176762937, 12725363193829, 204647839919537, 3291296999329711, 52931964429099939, 851279732514835940, 13690693829364308175
Offset: 1

Views

Author

R. H. Hardin Aug 19 2013

Keywords

Comments

Column 8 of A228285

Examples

			Some solutions for n=4
..1..0..0..0..1..0..1..0....1..0..0..1..0..0..1..0....1..0..0..0..1..0..0..0
..0..0..0..1..0..0..0..0....0..0..1..0..0..1..0..0....0..0..1..0..0..0..1..0
..0..0..0..0..0..1..0..0....0..0..0..0..1..0..0..0....0..0..0..0..0..0..0..0
..1..0..1..0..1..0..0..1....0..1..0..1..0..0..1..0....0..0..0..0..1..0..1..0
		

Crossrefs

See A228277-A228285, especially the latter.

Formula

a(n) = a(n-1) +170*a(n-2) +1243*a(n-3) +452*a(n-4) -25328*a(n-5) -47829*a(n-6) +329977*a(n-7) +677669*a(n-8) -3899000*a(n-9) -4142351*a(n-10) +40598266*a(n-11) -22625542*a(n-12) -280040412*a(n-13) +733571937*a(n-14) +225285263*a(n-15) -5406913431*a(n-16) +15244941445*a(n-17) -23143116063*a(n-18) +18064627845*a(n-19) +2246759550*a(n-20) -21472294755*a(n-21) +18258761486*a(n-22) +5172378119*a(n-23) -19704882159*a(n-24) +6931675953*a(n-25) +12628340471*a(n-26) -10036097232*a(n-27) -6485990080*a(n-28) +8290578844*a(n-29) +3493944338*a(n-30) -5396581563*a(n-31) -2482388885*a(n-32) +2807416030*a(n-33) +2023351213*a(n-34) -877760575*a(n-35) -1366907685*a(n-36) -211758176*a(n-37) +511379314*a(n-38) +405881894*a(n-39) +67901250*a(n-40) -105839886*a(n-41) -110007288*a(n-42) -59224072*a(n-43) -20510652*a(n-44) -4214944*a(n-45) -234085*a(n-46) +87637*a(n-47) -2782*a(n-48) -10138*a(n-49) -671*a(n-50) +608*a(n-51) +45*a(n-52) -30*a(n-53) -a(n-54) +a(n-55)

Extensions

Edited by N. J. A. Sloane, Aug 22 2013

A228284 Number of nX9 binary arrays with top left value 1 and no two ones adjacent horizontally, vertically or nw-se diagonally.

Original entry on oeis.org

34, 277, 9637, 186414, 4416695, 97268701, 2197847780, 49208639399, 1105411581741, 24801939723742, 556713719650007, 12494370307905104, 280426447918993931, 6293836975716291709, 141258681814255369288
Offset: 1

Views

Author

R. H. Hardin Aug 19 2013

Keywords

Comments

Column 9 of A228285

Examples

			Some solutions for n=4
..1..0..0..0..0..0..0..0..0....1..0..0..0..0..0..0..0..0
..0..0..0..1..0..0..1..0..0....0..0..0..1..0..0..1..0..0
..0..0..0..0..0..0..0..0..0....0..0..0..0..0..0..0..0..0
..0..0..1..0..1..0..1..0..1....0..0..1..0..1..0..0..1..0
		

Crossrefs

See A228277-A228285, especially the latter.

Formula

Satisfies a recurrence of order 89 (see link above) - see Zeilberger links in A228285 for a proof that this is correct, and for a g.f.

Extensions

Edited by N. J. A. Sloane, Aug 22 2013

A228481 Number of nX7 binary arrays with top left value 1 and no two ones adjacent horizontally, vertically or antidiagonally.

Original entry on oeis.org

13, 88, 1181, 13050, 152373, 1748684, 20185842, 232542935, 2680777055, 30897168815, 356129525933, 4104762592860, 47311923541451, 545321432832844, 6285425006257311, 72446383973495105, 835023655383918595
Offset: 1

Views

Author

R. H. Hardin Aug 22 2013

Keywords

Comments

Column 7 of A228482
Same recurrences as A228285 except in addition a smaller one for column 5

Examples

			Some solutions for n=4
..1..0..0..0..0..0..1....1..0..1..0..0..0..0....1..0..0..0..0..1..0
..0..0..0..0..0..0..0....0..0..0..0..0..1..0....0..0..0..1..0..0..0
..1..0..0..0..0..0..0....1..0..0..0..0..0..0....1..0..0..0..1..0..0
..0..0..1..0..0..1..0....0..1..0..1..0..0..1....0..0..0..0..0..0..0
		

Formula

a(n) = a(n-1) +85*a(n-2) +432*a(n-3) +192*a(n-4) -3711*a(n-5) -5096*a(n-6) +21164*a(n-7) +27340*a(n-8) -112654*a(n-9) -37244*a(n-10) +477721*a(n-11) -464722*a(n-12) -897815*a(n-13) +3102284*a(n-14) -4149918*a(n-15) +2761082*a(n-16) -138325*a(n-17) -1353257*a(n-18) +942033*a(n-19) +64683*a(n-20) -365483*a(n-21) +80904*a(n-22) +92350*a(n-23) -27097*a(n-24) -23292*a(n-25) +2585*a(n-26) +5635*a(n-27) +1405*a(n-28) -561*a(n-29) -545*a(n-30) -173*a(n-31) -14*a(n-32) +5*a(n-33) +a(n-34)

A228477 Number of nX3 binary arrays with top left value 1 and no two ones adjacent horizontally, vertically or antidiagonally.

Original entry on oeis.org

2, 4, 14, 41, 127, 386, 1181, 3605, 11013, 33635, 102734, 313780, 958385, 2927208, 8940618, 27307464, 83405606, 254747013, 778077691, 2376494562, 7258563605, 22169941573, 67713990833, 206819875427, 631693101322, 1929389878184
Offset: 1

Views

Author

R. H. Hardin Aug 22 2013

Keywords

Comments

Column 3 of A228482
Same recurrences as A228285 except in addition a smaller one for column 5

Examples

			Some solutions for n=4
..1..0..1....1..0..1....1..0..0....1..0..0....1..0..0....1..0..0....1..0..0
..0..0..0....0..0..0....0..1..0....0..0..1....0..0..0....0..0..0....0..0..1
..1..0..1....0..0..0....0..0..0....1..0..0....1..0..1....0..0..0....1..0..0
..0..0..0....0..0..0....1..0..0....0..0..0....0..0..0....0..0..0....0..0..1
		

Formula

a(n) = a(n-1) +5*a(n-2) +4*a(n-3) -a(n-5).
G.f.: -x*(-2-2*x+x^3) / ( (1+x)*(x^4-x^3-3*x^2-2*x+1) ). - R. J. Mathar, Aug 25 2013

A228478 Number of n X 4 binary arrays with top left value 1 and no two ones adjacent horizontally, vertically or antidiagonally.

Original entry on oeis.org

3, 9, 41, 172, 728, 3084, 13050, 55252, 233875, 990055, 4191028, 17741339, 75101906, 317918500, 1345800258, 5696989354, 24116274286, 102088075950, 432155280235, 1829382955772, 7744072911728, 32781908823977, 138771103836595
Offset: 1

Views

Author

R. H. Hardin, Aug 22 2013

Keywords

Comments

Same recurrences as A228285 except in addition a smaller one for column 5.

Examples

			Some solutions for n=4:
..1..0..1..0....1..0..1..0....1..0..0..0....1..0..0..1....1..0..0..0
..0..0..0..1....0..0..0..0....0..1..0..1....0..0..0..0....0..0..0..0
..1..0..0..0....0..0..0..1....0..0..0..0....1..0..0..1....0..1..0..1
..0..1..0..0....0..1..0..0....0..1..0..1....0..1..0..0....0..0..0..0
		

Crossrefs

Column 4 of A228482.

Formula

a(n) = a(n-1) + 10*a(n-2) + 15*a(n-3) + 4*a(n-4) - 6*a(n-5) - a(n-6) + 3*a(n-7) - a(n-8).
Empirical g.f.: x*(3 + 6*x + 2*x^2 - 4*x^3 - x^4 + 3*x^5 - x^6) / (1 - x - 10*x^2 - 15*x^3 - 4*x^4 + 6*x^5 + x^6 - 3*x^7 + x^8). - Colin Barker, Sep 11 2018

A228479 Number of n X 5 binary arrays with top left value 1 and no two ones adjacent horizontally, vertically or antidiagonally.

Original entry on oeis.org

5, 19, 127, 728, 4354, 25699, 152373, 902042, 5342712, 31639786, 187379548, 1109702480, 6571916787, 38920392611, 230495519461, 1365047364511, 8084124028133, 47876038862427, 283532896714060, 1679146925634733
Offset: 1

Views

Author

R. H. Hardin, Aug 22 2013

Keywords

Comments

Same recurrences as A228285 except in addition this smaller one for this column.

Examples

			Some solutions for n=4:
..1..0..1..0..0....1..0..0..0..0....1..0..0..0..0....1..0..1..0..0
..0..0..0..1..0....0..0..0..0..1....0..0..0..0..0....0..0..0..1..0
..1..0..0..0..1....1..0..0..0..0....1..0..0..0..0....1..0..0..0..0
..0..0..1..0..0....0..0..0..0..0....0..0..0..1..0....0..1..0..0..1
		

Crossrefs

Column 5 of A228482.

Formula

Empirical: a(n) = 3*a(n-1) + 15*a(n-2) + 16*a(n-3) - 11*a(n-4) - 20*a(n-5) + 19*a(n-6) - 8*a(n-7) + a(n-9).
Empirical g.f.: x*(5 + 4*x - 5*x^2 - 18*x^3 + 16*x^4 - 6*x^5 + x^7) / (1 - 3*x - 15*x^2 - 16*x^3 + 11*x^4 + 20*x^5 - 19*x^6 + 8*x^7 - x^9). - Colin Barker, Sep 11 2018
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