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.

A263521 Number of (3+1)X(n+1) arrays of permutations of 0..n*4+3 filled by rows with each element moved a city block distance of 0 or 1, and rows and columns in increasing lexicographic order.

Original entry on oeis.org

23, 208, 2076, 18369, 158109, 1317780, 10791350, 87194833, 698250904, 5555688785, 44005119429, 347432212188, 2736799922735, 21523189213085, 169068961542156, 1326964403390558, 10408686351322363, 81610767953922967, 639685545725575292
Offset: 1

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Author

R. H. Hardin, Oct 19 2015

Keywords

Comments

Row 3 of A263519.

Examples

			Some solutions for n=4
..0..1..2..3..4....0..1..2..3..4....0..1..2..8..9....0..2..3..8..9
.10..5.12..8.14....6..5..7.13..9....5..6..7..3..4....5..1..6..7..4
.15..6..7.18..9...15.10.12..8.14...10.11.12.13.14...11.10.17.12.13
.16.11.17.13.19...16.11.17.19.18...15.16.17.19.18...15.16.18.19.14
		

Crossrefs

Cf. A263519.

Formula

Empirical: a(n) = 18*a(n-1) -83*a(n-2) -203*a(n-3) +2162*a(n-4) -633*a(n-5) -21640*a(n-6) +20040*a(n-7) +120424*a(n-8) -126960*a(n-9) -418440*a(n-10) +397224*a(n-11) +935858*a(n-12) -706132*a(n-13) -1333426*a(n-14) +768238*a(n-15) +1198092*a(n-16) -535990*a(n-17) -670920*a(n-18) +245400*a(n-19) +229128*a(n-20) -73408*a(n-21) -45880*a(n-22) +13832*a(n-23) +4959*a(n-24) -1502*a(n-25) -235*a(n-26) +77*a(n-27) +2*a(n-28) -a(n-29)