login

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 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A219078
T(n,k)=Hilltop maps: number of nXk binary arrays indicating the locations of corresponding elements not exceeded by any horizontal, diagonal or antidiagonal neighbor in a random 0..1 nXk array
14
1, 3, 1, 5, 11, 1, 9, 47, 41, 1, 17, 165, 337, 149, 1, 31, 625, 2321, 2469, 547, 1, 57, 2435, 17537, 32945, 18499, 2007, 1, 105, 9367, 134809, 494713, 477309, 137251, 7361, 1, 193, 35901, 1023441, 7561349, 14228041, 6879341, 1019123, 27001, 1, 355, 137865
OFFSET
1,2
COMMENTS
Table starts
.1.......3...........5..............9.................17....................31
.1......11..........47............165................625..................2435
.1......41.........337...........2321..............17537................134809
.1.....149........2469..........32945.............494713...............7561349
.1.....547.......18499.........477309...........14228041.............433704331
.1....2007......137251........6879341..........407374825...........24734141495
.1....7361.....1019123.......99118753........11660290321.........1410242020653
.1...27001.....7573641.....1428782305.......333882416305........80444813963129
.1...99043....56263253....20594013941......9559854123673......4588436794733591
.1..363299...417979331...296830835781....273717397488937....261712432286491659
.1.1332617..3105269893..4278398369137...7837125931615553..14927540586501299193
.1.4888173.23069495037.61667023808785.224393896465841065.851435525780779197693
LINKS
EXAMPLE
Some solutions for n=3 k=4
..1..1..0..0....1..1..1..1....1..0..0..1....1..1..1..1....0..0..1..1
..0..0..1..0....1..0..0..1....1..1..0..0....1..1..1..0....1..1..1..0
..0..1..0..0....1..1..0..1....1..0..1..1....0..1..0..1....0..0..0..1
CROSSREFS
Column 2 is A218348
Row 1 is A000213(n+1)
Sequence in context: A093905 A324017 A063853 * A266033 A105064 A073496
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin Nov 11 2012
STATUS
approved