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 1-7 of 7 results.

A196140 Number of nX2 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 3,0,4,1,2 for x=0,1,2,3,4.

Original entry on oeis.org

3, 5, 8, 17, 34, 62, 123, 243, 471, 924, 1817, 3558, 6978, 13697, 26865, 52699, 103398, 202847, 397944, 780720, 1531657, 3004865, 5895113, 11565346, 22689467, 44513380, 87328672, 171325871, 336115955, 659409701, 1293664016, 2537976953, 4979134498
Offset: 1

Views

Author

R. H. Hardin Sep 28 2011

Keywords

Comments

Every 0 is next to 0 3's, every 1 is next to 1 0's, every 2 is next to 2 4's, every 3 is next to 3 1's, every 4 is next to 4 2's
Column 2 of A196146

Examples

			Some solutions for n=4
.1.0...0.1...1.0...0.0...0.1...1.0...1.0...1.0...0.0...1.1
.1.0...1.3...3.1...0.0...0.1...1.1...1.0...3.1...1.1...0.0
.1.1...3.1...1.1...0.0...1.1...0.1...1.0...1.3...1.1...0.0
.0.1...1.0...0.0...1.1...1.0...0.1...1.0...0.1...0.0...0.0
		

Formula

Empirical: a(n) = 2*a(n-1) +a(n-3) -2*a(n-4) -a(n-5) +a(n-6)

A196141 Number of n X 3 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 3,0,4,1,2 for x=0,1,2,3,4.

Original entry on oeis.org

4, 8, 7, 26, 49, 85, 178, 348, 683, 1349, 2688, 5319, 10498, 20818, 41206, 81574, 161646, 320215, 634294, 1256481, 2489029, 4930656, 9767642, 19350237, 38333645, 75940498, 150441579, 298031468, 590414638, 1169642000, 2317123308, 4590345948
Offset: 1

Views

Author

R. H. Hardin, Sep 28 2011

Keywords

Comments

Every 0 is next to 0 3's, every 1 is next to 1 0's, every 2 is next to 2 4's, every 3 is next to 3 1's, every 4 is next to 4 2's.
Column 3 of A196146.

Examples

			Some solutions for n=4:
.0.1.1...1.1.0...0.0.0...1.0.0...1.0.1...0.0.1...0.0.1
.1.1.0...0.1.1...1.1.1...3.1.1...1.0.1...0.0.1...1.1.1
.3.1.1...1.1.3...1.1.3...1.1.1...1.0.1...0.0.1...1.1.0
.1.0.1...1.0.1...0.0.1...0.0.0...1.0.1...0.0.1...0.1.1
		

Crossrefs

Cf. A196146.

Formula

Empirical: a(n) = 3*a(n-1) -2*a(n-2) +a(n-3) -3*a(n-4) +3*a(n-5) -a(n-6) -7*a(n-8) +a(n-9) +4*a(n-10) +2*a(n-11) +6*a(n-12).
Empirical g.f.: x*(4 - 4*x - 9*x^2 + 17*x^3 - 11*x^4 - 5*x^5 - 4*x^6 + 14*x^8 + 4*x^9 + 12*x^10) / (1 - 3*x + 2*x^2 - x^3 + 3*x^4 - 3*x^5 + x^6 + 7*x^8 - x^9 - 4*x^10 - 2*x^11 - 6*x^12). - Colin Barker, May 08 2018
Empirical formulas verified: see link. - Robert Israel, Jan 21 2019

A196143 Number of nX5 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 3,0,4,1,2 for x=0,1,2,3,4.

Original entry on oeis.org

8, 34, 49, 168, 481, 1031, 2781, 7666, 19581, 50767, 133067, 347285, 908050, 2376097, 6205040, 16210548, 42388933, 110845205, 289736000, 757344081, 1979883152, 5176072691, 13531879986, 35376145849, 92481993251, 241773334844
Offset: 1

Views

Author

R. H. Hardin Sep 28 2011

Keywords

Comments

Every 0 is next to 0 3's, every 1 is next to 1 0's, every 2 is next to 2 4's, every 3 is next to 3 1's, every 4 is next to 4 2's
Column 5 of A196146

Examples

			Some solutions for n=4
.1.0.0.0.0...0.1.1.0.1...1.0.1.1.1...1.1.1.1.1
.3.1.1.1.1...0.1.1.0.1...3.1.1.0.0...0.0.0.0.0
.1.3.3.1.3...0.1.1.0.1...1.1.1.0.0...0.0.0.0.0
.0.1.1.0.1...0.1.1.0.1...0.0.1.1.1...1.1.1.1.1
		

Formula

Empirical: a(n) = 5*a(n-1) -9*a(n-2) +12*a(n-3) -14*a(n-4) +5*a(n-5) +10*a(n-6) -69*a(n-7) +129*a(n-8) -145*a(n-9) +164*a(n-10) -196*a(n-11) +218*a(n-12) +394*a(n-13) -349*a(n-14) +295*a(n-15) -1023*a(n-16) +924*a(n-17) -298*a(n-18) +1097*a(n-19) -4595*a(n-20) -2208*a(n-21) +627*a(n-22) +2723*a(n-23) -690*a(n-24) -19588*a(n-25) +6132*a(n-26) +2659*a(n-27) +23034*a(n-28) +3305*a(n-29) +847*a(n-30) +42867*a(n-31) +37263*a(n-32) +85485*a(n-33) +47600*a(n-34) +98716*a(n-35) +83847*a(n-36) +39595*a(n-37) -5290*a(n-38) -194971*a(n-39) -247776*a(n-40) -380416*a(n-41) -386837*a(n-42) -332348*a(n-43) -375756*a(n-44) -286048*a(n-45) -312418*a(n-46) -286684*a(n-47) -274384*a(n-48) -251047*a(n-49) -167220*a(n-50) -126756*a(n-51) -65057*a(n-52) -32030*a(n-53) -7322*a(n-54) -100*a(n-55) +2812*a(n-56) +408*a(n-57) +568*a(n-58) -264*a(n-59) +32*a(n-61)

A196144 Number of nX6 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 3,0,4,1,2 for x=0,1,2,3,4.

Original entry on oeis.org

12, 62, 85, 346, 1031, 2599, 7486, 22292, 61689, 177057, 510032, 1448637, 4132242, 11862868, 33916712, 96889032, 277372934, 794009775, 2271276412, 6499360165, 18601549495, 53231495224, 152336019308, 435981877255, 1247751132201
Offset: 1

Views

Author

R. H. Hardin Sep 28 2011

Keywords

Comments

Every 0 is next to 0 3's, every 1 is next to 1 0's, every 2 is next to 2 4's, every 3 is next to 3 1's, every 4 is next to 4 2's
Column 6 of A196146

Examples

			Some solutions for n=4
.1.1.3.1.0.0...1.1.0.0.0.0...0.0.1.1.0.0...0.0.0.0.0.1
.0.0.1.1.0.0...0.1.1.1.1.1...1.1.3.3.1.1...1.1.1.1.1.1
.0.0.1.1.0.0...1.1.1.1.1.1...3.1.1.1.1.1...3.1.1.1.1.0
.0.0.1.3.1.1...1.0.0.0.0.0...1.0.0.0.0.0...1.0.0.0.1.1
		

A196145 Number of nX7 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 3,0,4,1,2 for x=0,1,2,3,4.

Original entry on oeis.org

17, 123, 178, 865, 2781, 7486, 24615, 85533, 266059, 866323, 2817802, 9024682, 29161693, 94823673, 306912929, 992919095, 3216924395, 10417479713, 33734415945, 109304966265, 354134153161, 1147139951832, 3716343382506
Offset: 1

Views

Author

R. H. Hardin Sep 28 2011

Keywords

Comments

Every 0 is next to 0 3's, every 1 is next to 1 0's, every 2 is next to 2 4's, every 3 is next to 3 1's, every 4 is next to 4 2's
Column 7 of A196146

Examples

			Some solutions for n=4
.1.0.0.1.1.0.0...1.3.1.0.0.0.1...1.0.0.1.1.0.1
.3.1.1.1.1.1.1...0.1.1.0.0.0.1...3.1.1.3.3.1.1
.1.1.1.0.0.1.1...0.1.1.1.1.1.1...1.1.1.1.1.1.0
.0.0.1.1.1.1.0...1.1.0.1.3.1.0...0.0.0.0.0.1.1
		

A196139 Number of n X n 0..4 arrays with each element x equal to the number of its horizontal and vertical neighbors equal to 3,0,4,1,2 for x=0,1,2,3,4.

Original entry on oeis.org

1, 5, 7, 83, 481, 2599, 24615, 330889, 4431097, 82611569, 1973678929, 55783136985
Offset: 1

Views

Author

R. H. Hardin Sep 28 2011

Keywords

Comments

Every 0 is next to 0 3's, every 1 is next to 1 0's, every 2 is next to 2 4's, every 3 is next to 3 1's, every 4 is next to 4 2's
Diagonal of A196146

Examples

			Some solutions for n=4
.1.3.1.0...0.1.3.1...1.3.1.0...0.0.1.1...0.1.1.0
.0.1.1.0...0.1.1.0...0.1.1.0...1.1.1.0...1.1.1.1
.1.1.1.1...0.1.1.0...0.1.1.1...3.1.1.0...1.0.0.1
.1.0.0.1...1.3.1.0...1.1.0.1...1.0.1.1...1.0.0.1
		

A196142 Number of nX4 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 3,0,4,1,2 for x=0,1,2,3,4.

Original entry on oeis.org

5, 17, 26, 83, 168, 346, 865, 2055, 4745, 10866, 24967, 57786, 134514, 312597, 722915, 1670991, 3869674, 8969607, 20789120, 48159310, 111529135, 258315343, 598428365, 1386426078, 3211799633, 7440009880, 17234511484, 39924363651, 92487922123
Offset: 1

Views

Author

R. H. Hardin Sep 28 2011

Keywords

Comments

Every 0 is next to 0 3's, every 1 is next to 1 0's, every 2 is next to 2 4's, every 3 is next to 3 1's, every 4 is next to 4 2's
Column 4 of A196146

Examples

			Some solutions for n=5
.0.1.3.1...0.1.1.0...0.1.3.1...1.0.0.1...0.0.0.1
.0.1.1.0...1.1.1.1...0.1.1.0...1.1.1.1...0.0.0.1
.1.3.1.0...1.0.0.1...1.3.3.1...0.1.1.0...1.1.1.3
.1.3.1.0...1.1.1.1...3.1.1.1...0.1.1.0...1.1.1.1
.0.1.3.1...0.1.1.0...1.0.0.0...1.3.1.0...0.0.0.0
		

Formula

Empirical: a(n) = 5*a(n-1) -9*a(n-2) +9*a(n-3) -8*a(n-4) +12*a(n-5) -20*a(n-6) -a(n-7) +21*a(n-8) +5*a(n-9) -11*a(n-10) -60*a(n-11) +128*a(n-12) +17*a(n-13) -20*a(n-14) -77*a(n-15) +15*a(n-16) -15*a(n-17) -28*a(n-18) -32*a(n-19) -118*a(n-20) +28*a(n-21) -65*a(n-22) -17*a(n-23) -22*a(n-24) +12*a(n-25) -15*a(n-26) +3*a(n-28)
Showing 1-7 of 7 results.