18098

Appears in sequences

• Number of n X n binary arrays symmetric under horizontal and vertical reflection with all ones connected only in a 11000-01111-11000 pattern in any orientation.at n=16A147454
• Number of permutations of 1..n containing the relative rank sequence { 164532 } at any spacing.at n=3A159138
• Number of nondecreasing arrangements of n+2 numbers in 0..3 with each number being the sum mod 4 of two others.at n=43A183906
• Number of (n+2)X(n+2) 0..1 arrays with every 3X3 subblock sum of the two maximums of the diagonal and antidiagonal minus the sum of the minimums of the central row and column nondecreasing horizontally and vertically.at n=1A254299
• Number of (n+2)X(2+2) 0..1 arrays with every 3X3 subblock sum of the two maximums of the diagonal and antidiagonal minus the sum of the minimums of the central row and column nondecreasing horizontally and vertically.at n=1A254300
• T(n,k)=Number of (n+2)X(k+2) 0..1 arrays with every 3X3 subblock sum of the two maximums of the diagonal and antidiagonal minus the sum of the minimums of the central row and column nondecreasing horizontally and vertically.at n=4A254306
• Number of (n+2)X(5+2) 0..1 arrays with every 3X3 subblock sum of the two sums of the diagonal and antidiagonal minus the two minimums of the central column and central row nondecreasing horizontally, vertically and ne-to-sw antidiagonally.at n=34A254904
• a(n) = 2*n^5 - floor(2^(1/5)*n)^5.at n=9A257855
• a(n) is the number of canonical polygons with 4n edges containing only right angles.at n=10A307391
• a(n) is the n-th nonnegative number to light exactly n segments when displayed on a calculator.at n=23A339700