login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 56th year, we are closing in on 350,000 sequences, and we’ve crossed 9,700 citations (which often say “discovered thanks to the OEIS”).

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A195280 Number of lower triangles of a 4X4 integer array with each element differing from all of its vertical and horizontal neighbors by n or less and triangles differing by a constant counted only once 1
6939, 626525, 12608631, 119743353, 724789395, 3249312469, 11755976175, 36215968241, 98454861067, 242177297229, 548894457959, 1162058315625, 2322243189891, 4416808121541, 8048123047903, 14125147709409, 23983914638075 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 4 of A195278

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..169

FORMULA

Empirical: a(n) = (49024/315)*n^9 + (24512/35)*n^8 + (457792/315)*n^7 + (81824/45)*n^6 + (67912/45)*n^5 + (38756/45)*n^4 + (11832/35)*n^3 + (27752/315)*n^2 + (1454/105)*n + 1

EXAMPLE

Some solutions for n=5

...0............0............0............0............0............0

..-1.-2.........1..1.........5..3.........3..1........-1.-3.........3..4

..-6.-5.-6.....-2..2.-1......5..3..1......7..4..2......1..1.-2......0..4..1

..-2.-1.-1..1...3..6..2..0...1.-2..3..1...5..3.-2.-1..-2..2..1..1..-5..0..2..1

CROSSREFS

Sequence in context: A004244 A253736 A004245 * A059462 A252432 A072870

Adjacent sequences:  A195277 A195278 A195279 * A195281 A195282 A195283

KEYWORD

nonn

AUTHOR

R. H. Hardin Sep 14 2011

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified December 5 16:34 EST 2021. Contains 349557 sequences. (Running on oeis4.)