18998

Appears in sequences

• Number of terms in 5th derivative of a function composed with itself n times.at n=22A022815
• Number of compositions of n such that two adjacent parts are not equal modulo 4.at n=20A062202
• a(n) = 36*n^2 - 2*n.at n=22A158062
• Generating primitive Pythagorean triangles by using (n, n+1) gives perimeters for each n. This sequence lists the sum of these perimeters for each n triangles.at n=22A193068
• Number T(n,k) of tilings of a 5 X n rectangle with pentominoes of any shape and exactly k pentominoes of shape N; triangle T(n,k), n>=0, read by rows.at n=12A247705
• Number of tilings of a 5 X n rectangle using n pentominoes of any but the N shape.at n=6A247769
• Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 253", based on the 5-celled von Neumann neighborhood.at n=29A271052
• Number T(n,k) of sets of exactly k nonempty words with a total of n letters over n-ary alphabet such that within each prefix of a word every letter of the alphabet is at least as frequent as the subsequent alphabet letter; triangle T(n,k), n>=0, read by rows.at n=47A293815
• Number of sets of exactly three nonempty words with a total of n letters over n-ary alphabet such that within each prefix of a word every letter of the alphabet is at least as frequent as the subsequent alphabet letter.at n=7A293965
• First term of n-th difference sequence of (floor(k*r)), r = -sqrt(2), k >= 0.at n=16A325665
• Products k of 4 distinct primes (or tetraprimes) such that k has no squarefree neighbors.at n=27A364141
• Products k of 4 distinct primes (or tetraprimes) such that none of k-2, k-1, k+1 and k+2 is squarefree.at n=11A364766
• a(0) = 1; a(n) = a(n-1) - Sum_{k=0..n-1} k * a(k) * a(n-1-k).at n=11A386473