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”).

A222148
Number of binary arrays indicating the locations of trailing edge maxima of a random length-n 0..3 array extended with zeros and convolved with 1,-2,1
1
2, 4, 8, 15, 27, 47, 79, 131, 216, 355, 582, 952, 1554, 2531, 4114, 6679, 10835, 17568, 28474, 46136, 74732, 121021, 195940, 317190, 513415, 830965, 1344839, 2176388, 3521960, 5699251, 9222308, 14922891, 24146832, 39071752, 63221132, 102296095
OFFSET
1,1
COMMENTS
Column 3 of A222153
LINKS
FORMULA
Empirical: a(n) = 6*a(n-1) -14*a(n-2) +15*a(n-3) -5*a(n-4) -4*a(n-5) +4*a(n-6) +a(n-7) -12*a(n-8) +27*a(n-9) -25*a(n-10) +a(n-11) +14*a(n-12) -7*a(n-13) -3*a(n-15) +7*a(n-16) -13*a(n-17) +24*a(n-18) -21*a(n-19) +8*a(n-21) +6*a(n-22) -17*a(n-23) +13*a(n-24) -14*a(n-25) +21*a(n-26) -7*a(n-27) -11*a(n-28) +10*a(n-29) -7*a(n-30) +13*a(n-31) -17*a(n-32) -a(n-33) +16*a(n-34) -3*a(n-35) -4*a(n-36) -a(n-37) +3*a(n-38) +4*a(n-39) -13*a(n-40) +7*a(n-42) +a(n-43) +3*a(n-46) -2*a(n-47) -5*a(n-48) -a(n-49) +a(n-50) +a(n-51) +a(n-52) +a(n-53) +a(n-54)
EXAMPLE
Some solutions for n=7, one extended zero followed by filtered positions
..0....0....0....0....0....0....0....0....0....0....0....0....0....0....0....0
..1....0....0....0....0....0....1....1....1....1....1....0....0....1....1....0
..0....0....1....1....0....0....0....0....0....0....0....1....0....0....0....1
..0....0....0....0....1....0....1....0....0....1....1....0....0....0....0....0
..0....0....0....0....0....0....0....0....1....0....0....0....0....0....0....0
..0....1....0....0....0....1....1....0....0....1....0....0....0....1....0....0
..0....0....1....0....1....0....0....1....1....0....1....1....0....0....0....0
..1....1....0....0....0....0....0....0....0....0....0....0....1....0....1....0
..0....0....1....1....1....1....0....0....0....0....0....0....0....0....0....0
..1....1....0....0....0....0....1....1....0....0....0....0....1....1....0....1
CROSSREFS
Sequence in context: A328087 A001523 A222039 * A222040 A222149 A222041
KEYWORD
nonn
AUTHOR
R. H. Hardin Feb 09 2013
STATUS
approved