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A180985
Array T(n,k) = number of n X k binary matrices with rows and columns in lexicographically nondecreasing order.
8
2, 3, 3, 4, 7, 4, 5, 14, 14, 5, 6, 25, 45, 25, 6, 7, 41, 130, 130, 41, 7, 8, 63, 336, 650, 336, 63, 8, 9, 92, 785, 2942, 2942, 785, 92, 9, 10, 129, 1682, 11819, 24520, 11819, 1682, 129, 10, 11, 175, 3351, 42305, 183010, 183010, 42305, 3351, 175, 11, 12, 231, 6280, 136564
OFFSET
1,1
COMMENTS
Differs from "number of inequivalent {0,1}-matrices of size n X k, modulo permutations of rows and columns", A241956, starting at T(2, 3) = 14 while A241956(2, 3) = 13. - M. F. Hasler, Apr 27 2022
FORMULA
T(n,k) = T(k,n). T(1,k) = k+1. T(2,k) = A004006(k+1). T(3,k) = A184138(k). - M. F. Hasler, Apr 27 2022
EXAMPLE
Table starts:
..2...3.....4.......5.........6...........7.............8................9
..3...7....14......25........41..........63............92..............129
..4..14....45.....130.......336.........785..........1682.............3351
..5..25...130.....650......2942.......11819.........42305...........136564
..6..41...336....2942.....24520......183010.......1202234..........6979061
..7..63...785...11819....183010.....2625117......33345183........371484319
..8..92..1682...42305...1202234....33345183.....836488618......18470742266
..9.129..3351..136564...6979061...371484319...18470742266.....818230288201
.10.175..6280..402910..36211867..3651371519..358194085968...31887670171373
.11.231.11176.1099694.170079565.32017940222.6148026957098.1096628939510047
.
All solutions for 3 X 3:
..0..0..0....0..0..0....0..0..0....0..0..0....0..0..0....0..0..0....0..0..0
..0..0..0....0..0..0....0..0..1....0..0..1....0..0..1....0..1..1....0..0..0
..0..0..1....0..1..1....0..1..0....0..0..1....0..1..1....0..1..1....1..1..1
.
..0..0..0....0..0..0....0..0..0....0..0..0....0..0..0....0..0..1....0..0..1
..0..0..1....0..1..1....0..0..1....0..1..1....0..1..1....0..1..0....0..1..0
..1..1..0....1..0..0....1..1..1....1..0..1....1..1..1....0..1..0....0..1..1
.
..0..0..1....0..0..1....0..0..1....0..0..1....0..0..1....0..0..1....0..0..1
..0..0..1....0..0..1....0..0..1....0..1..1....0..1..0....0..1..0....0..1..0
..0..1..0....0..0..1....0..1..1....0..1..1....1..0..0....1..1..0....1..0..1
.
..0..0..1....0..0..1....0..0..1....0..0..1....0..0..1....0..0..1....0..0..1
..0..1..0....0..0..1....0..1..1....0..1..1....0..0..1....0..1..1....0..1..1
..1..1..1....1..1..0....1..0..0....1..1..0....1..1..1....1..0..1....1..1..1
.
..0..0..0....0..0..1....0..0..1....0..0..1....0..1..1....0..1..1....0..1..1
..1..1..1....1..1..0....1..1..0....1..1..1....0..1..1....0..1..1....0..1..1
..1..1..1....1..1..0....1..1..1....1..1..1....0..1..1....1..0..0....1..0..1
...
..0..1..1....0..1..1....0..1..1....0..1..1....0..1..1....0..1..1....0..1..1
..0..1..1....1..0..0....1..0..0....1..0..0....1..0..1....1..0..1....1..0..1
..1..1..1....1..0..0....1..0..1....1..1..1....1..1..0....1..0..1....1..1..1
.
..0..1..1....1..1..1
..1..1..1....1..1..1
..1..1..1....1..1..1
PROG
(PARI) A180985(h, w, cnt=0)={ local(A=matrix(h, w), z(r, c)=!while(r<h, A[r++, c]==A[r, c-1]||return)); while(cnt++, for(r=1, h, for(c=1, w, A[r, c] && next; A[r, c]=1; while(c>1 && z(r, c), c--); while(c>1, A[r, c--]=0); while(r>1, A[r--, ]=A[r+1, ]); next(3))); break); cnt} \\ M. F. Hasler, Apr 27 2022
CROSSREFS
Cf. A089006 (diagonal).
Cf. A004006 (row & column 2), A184138 (row & column 3).
Cf. A241956 (similar but different).
Sequence in context: A248944 A267245 A266428 * A227385 A049790 A222188
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, Sep 30 2010
STATUS
approved