19272

Appears in sequences

• a(n) = number of (s(0), s(1), ..., s(n)) such that s(i) is an integer, s(0) = 0, |s(1)| = 1, |s(i) - s(i-1)| <= 1 for i >= 2, s(n) = 4. Also a(n) = T(n,n-4), where T is the array defined in A025177.at n=8A025182
• Structured truncated tetrahedral numbers.at n=21A100156
• Weight distribution of [73,37,13] binary quadratic-residue (or QR) code.at n=15A145982
• Number of 3-step one or two space at a time rook's tours on an n X n board summed over all starting positions.at n=19A187288
• Number of 1X7 integer matrices with each row summing to zero, row elements in nondecreasing order, rows in lexicographically nondecreasing order, and the sum of squares of the elements <= 2*n^2 (number of collections of 1 zero-sum 7-vectors with total modulus squared not more than 2*n^2, ignoring vector and component permutations).at n=11A192694
• Triangle read by rows: T(n,k) is the number of Dyck paths of semilength n (n>=1) having k (0<=k<=n-1) upper interactions.at n=61A247285
• Number of partitions of n in which two summands (of each size) are designated.at n=25A255180
• Numbers k such that A090086(k), the smallest pseudoprime to base k (not necessarily exceeding k), is a Carmichael number.at n=28A293203
• Partial sums of A299257.at n=29A299263
• Number T(n,k) of partitions of [n] having k blocks containing their own index when blocks are ordered with decreasing largest elements; triangle T(n,k), n>=0, 0<=k<=ceiling(n/2), read by rows.at n=52A350647
• Triangular array read by rows. T(n,k) is the number of n X n Boolean matrices with row rank k, n >= 0, 0 <= k <= n.at n=14A354741
• a(n) = sum of the first n primes whose distance to next prime is 4.at n=41A360226