22224

Appears in sequences

• Number of partially labeled rooted trees with n nodes (3 of which are labeled).at n=5A000444
• Triangle read by rows: T(n,k) is the number of partially labeled rooted trees with n vertices, k of which are labeled, 0 <= k <= n.at n=39A008295
• Numbers whose set of base-9 digits is {3,4}.at n=34A032833
• Numbers having four 3's in base 9.at n=25A043468
• Numbers having four 2's in base 10.at n=11A043500
• First member of the Diophantine pair (m,k) that satisfies 7*(m^2+m) = k^2+k; a(n)=m.at n=8A077398
• Antidiagonal sums of symmetric square table A085484, in which the main diagonal is equal to the first row shift left.at n=7A085486
• Lunar fourth powers: n*n*n*n, where * is lunar multiplication.at n=24A087051
• Triangle read by rows: T(n,k) is the number of hill-free Schroeder paths of length 2n that have k returns to the x-axis (0<=k<=floor(n/2)). A Schroeder path of length 2n is a lattice path from (0,0) to (2n,0) consisting of U=(1,1), D=(1,-1) and H=(2,0) steps and never going below the x-axis. A hill is a peak at height 1.at n=40A114692
• Sequence t_n arising in enumeration of arrays of directed blocks (see Quaintance reference for precise definition).at n=12A129875
• Number of obtuse isosceles triangles on an n X n grid.at n=16A190318
• For k in {2,3,...,9} define a sequence as follows: a(0)=0; for n>=0, a(n+1)=a(n)+1, unless a(n) ends in k, in which case a(n+1) is obtained by replacing the last digit of a(n) with the digit(s) of k^2. This is k(4).at n=40A237341
• Numbers n such that digits of n are not present in n^8.at n=15A253606
• Numbers with digits 2 and 4 only.at n=31A284920
• Multiples of 1852.at n=12A303272
• Numbers with no 0 digit that are divisible by the sum of any two of their digits at distinct positions.at n=40A308561
• Number of set partitions of {1,...,n} where each block's elements are pairwise coprime.at n=15A320423
• Positive numbers k such that k and k + 1 are both positive negaFibonacci-Niven numbers (A331085) and -k and -(k + 1) are both negative negaFibonacci-Niven numbers (A331088).at n=35A331092