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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A222003 Number of nX5 arrays with each row a permutation of 1..5 having at least as many downsteps as the preceding row, with rows in lexicographically nonincreasing order 1
120, 3853, 78376, 1227685, 16011558, 180224522, 1788225862, 15883318341, 127864299298, 942615276569, 6419292213136, 40684542916124, 241500003506194, 1349966084204199, 7140088927351586, 35880243705890673, 171932038247810370 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 5 of A222005

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..210

FORMULA

Empirical: a(n) = 66*a(n-1) -2145*a(n-2) +45760*a(n-3) -720720*a(n-4) +8936928*a(n-5) -90858768*a(n-6) +778789440*a(n-7) -5743572120*a(n-8) +37014131440*a(n-9) -210980549208*a(n-10) +1074082795968*a(n-11) -4922879481520*a(n-12) +20448884000160*a(n-13) -77413632286320*a(n-14) +268367258592576*a(n-15) -855420636763836*a(n-16) +2515943049305400*a(n-17) -6848956078664700*a(n-18) +17302625882942400*a(n-19) -40661170824914640*a(n-20) +89067326568860640*a(n-21) -182183167981760400*a(n-22) +348524321356411200*a(n-23) -624439409096903400*a(n-24) +1049058207282797712*a(n-25) -1654284096099796392*a(n-26) +2450791253481179840*a(n-27) -3413602103063071920*a(n-28) +4472995859186094240*a(n-29) -5516694892996182896*a(n-30) +6406484391866534976*a(n-31) -7007092303604022630*a(n-32) +7219428434016265740*a(n-33) -7007092303604022630*a(n-34) +6406484391866534976*a(n-35) -5516694892996182896*a(n-36) +4472995859186094240*a(n-37) -3413602103063071920*a(n-38) +2450791253481179840*a(n-39) -1654284096099796392*a(n-40) +1049058207282797712*a(n-41) -624439409096903400*a(n-42) +348524321356411200*a(n-43) -182183167981760400*a(n-44) +89067326568860640*a(n-45) -40661170824914640*a(n-46) +17302625882942400*a(n-47) -6848956078664700*a(n-48) +2515943049305400*a(n-49) -855420636763836*a(n-50) +268367258592576*a(n-51) -77413632286320*a(n-52) +20448884000160*a(n-53) -4922879481520*a(n-54) +1074082795968*a(n-55) -210980549208*a(n-56) +37014131440*a(n-57) -5743572120*a(n-58) +778789440*a(n-59) -90858768*a(n-60) +8936928*a(n-61) -720720*a(n-62) +45760*a(n-63) -2145*a(n-64) +66*a(n-65) -a(n-66)

EXAMPLE

Some solutions for n=3

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

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

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

CROSSREFS

Sequence in context: A052722 A282612 A231136 * A139389 A166596 A000514

Adjacent sequences:  A222000 A222001 A222002 * A222004 A222005 A222006

KEYWORD

nonn

AUTHOR

R. H. Hardin Feb 03 2013

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 May 31 22:45 EDT 2020. Contains 334756 sequences. (Running on oeis4.)