21608

Appears in sequences

• Starting from generation 8 add previous and next term yielding generation 9.at n=22A048455
• Values of n^2 - 1 resulting from A050795.at n=13A050799
• a(0)=1, a(n) = 8*n*(2*n-1).at n=37A067239
• Numbers k such that tau(k) - tau(k+1) = 1.at n=26A068208
• Expansion of q^(-1/2)(eta(q^2)eta(q^10)/(eta(q)eta(q^5)))^2 in powers of q.at n=28A093830
• Triangle read by rows: T(n,k) (0<=k<=n) is the number of Delannoy paths of length n, having k (1,1)-steps on the lines y=x, y=x+1 and y=x-1.at n=40A110183
• a(n) = the smallest multiple of the n-th prime such that (a(n)-1) is divisible by both the (n-1)th prime and the (n+1)st prime.at n=10A143244
• a(n) = 4*(3*n+1)*(3*n+2).at n=24A144410
• Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, 1), (-1, 0, 0), (0, 0, -1), (1, 0, 0), (1, 1, 0)}.at n=8A150322
• Eight times hexagonal numbers: a(n) = 8*n*(2*n-1).at n=37A152750
• Number of n X 5 binary arrays with all 1s connected, a path of 1s from upper left corner to lower right corner, and no 1 having more than two 1s adjacent.at n=6A163688
• Number of n X 7 binary arrays with all 1s connected, a path of 1s from upper left corner to lower right corner, and no 1 having more than two 1s adjacent.at n=4A163690
• a(n) = 9*7^n-1.at n=4A198690
• Number of -6..6 arrays x(0..n-1) of n elements with zero sum and no two consecutive declines, no adjacent equal elements, and no element more than one greater than the previous (random base sawtooth pattern).at n=11A200179
• Number of partitions p of n such that (number of numbers of the form 5k + 3 in p) is a part of p.at n=40A241552
• Irregular triangular array: row n gives numbers D, each being the discriminant of the minimal polynomial of a quadratic irrational represented by a continued fraction with period an n-tuple of 1s and 3s.at n=34A246921
• Triangle read by rows: Number of oriented graphs on n nodes with k components.at n=60A281446
• Numbers k such that k and k+1 have different (ordered) prime signatures and d_3(k) = d_3(k+1), where d_3 is A007425.at n=4A333057
• G.f. A(x) satisfies: A(x) = x + x^2 * A(x/(1 - 2*x)) / (1 - 2*x).at n=10A351028
• Partial sums of the ziggurat sequence A347186.at n=45A356351