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.

A249707 T(n,k)=Number of length n+3 0..k arrays with every four consecutive terms having the maximum of some two terms equal to the minimum of the remaining two terms.

Original entry on oeis.org

10, 39, 14, 100, 69, 20, 205, 208, 125, 28, 366, 485, 440, 221, 38, 595, 966, 1153, 896, 377, 52, 904, 1729, 2524, 2601, 1724, 659, 72, 1305, 2864, 4893, 6172, 5425, 3440, 1177, 100, 1810, 4473, 8688, 12789, 13666, 11925, 7056, 2119, 138, 2431, 6670, 14433
Offset: 1

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Author

R. H. Hardin, Nov 04 2014

Keywords

Comments

Table starts
..10...39...100....205.....366.....595.....904.....1305.....1810.....2431
..14...69...208....485.....966....1729....2864.....4473.....6670.....9581
..20..125...440...1153....2524....4893....8688....14433....22756....34397
..28..221...896...2601....6172...12789...24032....41937....69052...108493
..38..377..1724...5425...13666...29673...57912...104289...176350...283481
..52..659..3440..11925...32500...75495..156416...297321...528340...889339
..72.1177..7056..27113...80360..200489..442144...888465..1659976..2924889
.100.2119.14544..61725..198164..528755.1235840..2613945..5113060..9391327
.138.3805.29620.137593..474302.1341901.3295784..7275729.14775346.28054653
.190.6857.60416.307437.1140694.3434085.8902160.20616873.43717054.86348977

Examples

			Some solutions for n=6 k=4
..3....3....2....4....1....4....3....4....3....1....0....3....3....2....3....2
..1....3....4....1....4....2....3....1....4....1....2....0....3....1....3....1
..0....3....0....1....1....0....2....1....3....2....2....0....3....1....4....2
..1....2....2....1....1....2....4....1....0....1....3....0....4....0....0....4
..1....4....2....4....0....4....3....2....3....1....2....0....2....1....3....2
..1....3....2....1....3....2....3....1....3....1....1....0....3....3....3....1
..0....3....0....1....1....1....3....1....3....3....2....0....3....1....4....2
..4....3....4....1....1....2....2....1....1....1....3....0....4....1....3....4
..1....0....2....0....0....2....3....4....4....0....2....1....1....0....2....2
		

Crossrefs

Column 1 is A246473
Row 1 is A059722(n+1)

Formula

Empirical for column k:
k=1: a(n) = a(n-1) +a(n-4)
k=2: [order 10]
k=3: [order 17]
k=4: [order 24]
k=5: [order 30]
k=6: [order 37]
k=7: [order 43]
Empirical for row n:
n=1: a(n) = 2*n^3 + 4*n^2 + 3*n + 1
n=2: a(n) = (1/2)*n^4 + 4*n^3 + (11/2)*n^2 + 3*n + 1
n=3: a(n) = (1/15)*n^5 + 2*n^4 + 7*n^3 + 7*n^2 + (44/15)*n + 1
n=4: a(n) = (7/15)*n^5 + 5*n^4 + 11*n^3 + 8*n^2 + (38/15)*n + 1
n=5: a(n) = (5/3)*n^5 + 10*n^4 + 16*n^3 + 8*n^2 + (4/3)*n + 1
n=6: a(n) = (1/5)*n^6 + (73/15)*n^5 + 18*n^4 + 22*n^3 + (34/5)*n^2 - (13/15)*n + 1
n=7: a(n) = (1/70)*n^7 + (19/15)*n^6 + (178/15)*n^5 + 30*n^4 + (851/30)*n^3 + (56/15)*n^2 - (446/105)*n + 1