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 1-6 of 6 results.

A280955 Number of n X 2 0..2 arrays with no element equal to more than one of its horizontal, vertical and antidiagonal neighbors and with new values introduced in order 0 sequentially upwards.

Original entry on oeis.org

2, 9, 42, 205, 997, 4850, 23593, 114769, 558298, 2715861, 13211405, 64267362, 312630929, 1520804569, 7398009354, 35987886621, 175064388469, 851607109714, 4142673879353, 20152188344737, 98031056006074, 476875651282597
Offset: 1

Views

Author

R. H. Hardin, Jan 11 2017

Keywords

Examples

			Some solutions for n=4:
..0..1. .0..1. .0..1. .0..1. .0..1. .0..1. .0..0. .0..0. .0..1. .0..1
..0..2. .2..0. .1..2. .2..1. .2..2. .2..2. .1..1. .1..2. .2..2. .2..0
..1..0. .1..2. .0..2. .0..2. .1..0. .1..0. .2..2. .2..0. .1..0. .0..1
..0..1. .0..0. .1..1. .1..0. .1..0. .2..2. .0..1. .1..1. .0..2. .2..1
		

Crossrefs

Column 2 of A280961.

Formula

Empirical: a(n) = 4*a(n-1) + 4*a(n-2) + a(n-3) for n>4.
Empirical g.f.: x*(1 - x)*(1 + x)*(2 + x) / (1 - 4*x - 4*x^2 - x^3). - Colin Barker, Feb 15 2019

A280956 Number of nX3 0..2 arrays with no element equal to more than one of its horizontal, vertical and antidiagonal neighbors and with new values introduced in order 0 sequentially upwards.

Original entry on oeis.org

4, 42, 241, 1554, 9899, 63085, 402077, 2562733, 16334111, 104108376, 663554669, 4229292041, 26956196587, 171810442122, 1095066516245, 6979614612419, 44485900541127, 283539343806484, 1807191908208865, 11518481171610485
Offset: 1

Views

Author

R. H. Hardin, Jan 11 2017

Keywords

Comments

Column 3 of A280961.

Examples

			Some solutions for n=4
..0..1..0. .0..0..1. .0..1..2. .0..1..2. .0..1..0. .0..0..1. .0..1..1
..1..2..2. .2..2..0. .1..2..0. .2..0..0. .0..2..0. .2..1..2. .0..2..0
..0..1..0. .0..1..2. .0..1..2. .2..1..2. .2..1..2. .2..0..1. .1..0..1
..1..0..1. .1..0..2. .2..1..0. .0..0..1. .1..0..0. .0..2..2. .2..2..0
		

Crossrefs

Cf. A280961.

Formula

Empirical: a(n) = 5*a(n-1) +8*a(n-2) +5*a(n-3) +4*a(n-4) -35*a(n-5) +2*a(n-6) +71*a(n-7) -11*a(n-8) -38*a(n-9) +6*a(n-10) -8*a(n-11) -8*a(n-12) for n>16

A280957 Number of nX4 0..2 arrays with no element equal to more than one of its horizontal, vertical and antidiagonal neighbors and with new values introduced in order 0 sequentially upwards.

Original entry on oeis.org

11, 205, 1554, 14106, 126267, 1121528, 9986376, 88940022, 791997382, 7052519878, 62801413162, 559236961207, 4979918315253, 44345374930680, 394888443546716, 3516418473800700, 31313145020210260, 278838553941378885
Offset: 1

Views

Author

R. H. Hardin, Jan 11 2017

Keywords

Comments

Column 4 of A280961.

Examples

			Some solutions for n=4
..0..1..0..1. .0..0..1..1. .0..1..0..2. .0..1..0..1. .0..1..0..0
..2..0..1..2. .2..2..0..0. .0..2..1..1. .0..2..1..0. .0..1..2..1
..1..2..0..2. .0..1..2..1. .2..0..0..2. .1..0..2..2. .2..0..1..0
..0..2..1..0. .0..1..0..0. .1..2..1..0. .2..1..0..0. .0..2..2..1
		

Crossrefs

Cf. A280961.

Formula

Empirical: a(n) = 11*a(n-1) -25*a(n-2) +62*a(n-3) +6*a(n-4) -470*a(n-5) -199*a(n-6) -97*a(n-7) +1761*a(n-8) +1271*a(n-9) -4651*a(n-10) +16916*a(n-11) +28022*a(n-12) -48991*a(n-13) -17485*a(n-14) +9764*a(n-15) -403040*a(n-16) -181089*a(n-17) +1006721*a(n-18) +635719*a(n-19) -545439*a(n-20) +450907*a(n-21) +419840*a(n-22) -1904900*a(n-23) -1409770*a(n-24) +462471*a(n-25) -68469*a(n-26) -393605*a(n-27) +577614*a(n-28) +1161352*a(n-29) +807943*a(n-30) +65475*a(n-31) -70526*a(n-32) -17768*a(n-33) -450612*a(n-34) -560853*a(n-35) -288048*a(n-36) +109569*a(n-37) +243445*a(n-38) +191920*a(n-39) +25889*a(n-40) -30729*a(n-41) -31913*a(n-42) -14398*a(n-43) -9025*a(n-44) +830*a(n-45) +2189*a(n-46) +2423*a(n-47) +167*a(n-48) -140*a(n-49) -187*a(n-50) +2*a(n-51) +10*a(n-52) +4*a(n-53) -a(n-54) for n>57

A280958 Number of n X 5 0..2 arrays with no element equal to more than one of its horizontal, vertical and antidiagonal neighbors and with new values introduced in order 0 sequentially upwards.

Original entry on oeis.org

30, 997, 9899, 126267, 1599234, 20029500, 251270618, 3152475854, 39530438497, 495721552160, 6216700479112, 77962372076794, 977711970478121, 12261314459515967, 153766955348557489, 1928363669762835672
Offset: 1

Views

Author

R. H. Hardin, Jan 11 2017

Keywords

Comments

Column 5 of A280961.

Examples

			Some solutions for n=4
..0..1..2..1..0. .0..1..0..1..2. .0..1..0..0..2. .0..0..1..0..0
..0..2..0..2..1. .1..2..2..0..0. .1..2..1..2..0. .1..2..1..2..1
..1..1..0..2..0. .0..0..1..2..2. .2..0..0..1..0. .2..0..2..0..2
..0..2..1..0..1. .1..2..1..0..1. .1..1..2..1..2. .1..0..1..0..2
		

Crossrefs

Cf. A280961.

A280959 Number of nX6 0..2 arrays with no element equal to more than one of its horizontal, vertical and antidiagonal neighbors and with new values introduced in order 0 sequentially upwards.

Original entry on oeis.org

82, 4850, 63085, 1121528, 20029500, 346289502, 6052621154, 105777297118, 1846875100200, 32253949107668, 563278827019060, 9836989060923111, 171791531487108414, 3000138481060751984, 52393917402743354484
Offset: 1

Views

Author

R. H. Hardin, Jan 11 2017

Keywords

Comments

Column 6 of A280961.

Examples

			Some solutions for n=3
..0..1..0..1..2..1. .0..1..0..1..0..2. .0..1..0..0..2..2. .0..1..0..1..1..0
..2..0..1..0..2..1. .1..0..1..2..0..1. .2..1..2..1..0..1. .2..1..2..2..0..2
..1..2..0..1..0..0. .2..2..0..2..1..2. .0..2..1..2..2..1. .0..0..1..1..2..1
		

Crossrefs

Cf. A280961.

A280960 Number of nX7 0..2 arrays with no element equal to more than one of its horizontal, vertical and antidiagonal neighbors and with new values introduced in order 0 sequentially upwards.

Original entry on oeis.org

224, 23593, 402077, 9986376, 251270618, 6052621154, 148137367471, 3624578433814, 88500510514256, 2162800206884214, 52848406746190667, 1291317121466531838, 31553229218022226192, 770996700142671487457
Offset: 1

Views

Author

R. H. Hardin, Jan 11 2017

Keywords

Comments

Column 7 of A280961.

Examples

			Some solutions for n=2
..0..1..2..0..2..1..2. .0..1..2..0..1..0..2. .0..1..0..1..2..1..0
..0..2..1..2..0..2..0. .2..0..1..0..1..0..1. .0..1..2..0..2..0..2
		

Crossrefs

Cf. A280961.
Showing 1-6 of 6 results.