22351

Appears in sequences

• T(n,1) + T(n,2) + ... T(n,n), where T is the array in A026098.at n=31A026101
• Quasi-Carmichael numbers to base -5: squarefree composites n such that prime p|n ==> p+5|n+5.at n=7A029565
• Numbers k > 1 such that k mod ord2(k) is even, where ord2(k) is the order of 2 mod k.at n=33A036260
• a(n) = p^2 + p + 1 where p runs through the primes.at n=34A060800
• Numbers n such that n + sum of prime factors of n = (n+1) + sum of prime factors of (n+1).at n=23A075654
• Trajectory of 18 under iteration of the map k -> A087712(k).at n=28A077960
• Triangle read by rows: T(i,j) = (T(i-1,j) + i)*i.at n=22A121682
• 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, 1), (0, -1, 1), (0, 1, -1), (1, 1, 1)}.at n=8A149709
• Products of three distinct happy primes A035497.at n=31A154717
• Number of nodes (or order) of a graph model obtained using an automata scheme on sets of order prime(n) >= 5 and in which all not halt states are linked by arcs (edges).at n=33A160772
• Numbers that are repdigits with length > 2 in more than one base.at n=42A167783
• Partial sums of A061262.at n=33A176661
• Number of vertices in truncated tetrahedron with faces that are centered polygons.at n=15A193218
• Central polygonal numbers that are nontrivially the product of two central polygonal numbers.at n=14A203173
• Numbers arising in computing the Turan function of cycles of length 4.at n=38A217004
• Number of 6Xn -1,1 arrays such that the sum over i=1..6,j=1..n of i*x(i,j) is zero and rows are nondecreasing (ways to put n thrusters pointing east or west at each of 6 positions 1..n distance from the hinge of a south-pointing gate without turning the gate).at n=9A225313
• Least integer k such that the n-th prime of form m^2+1 divides the composite number k^2+1.at n=27A255675
• 50-gonal numbers: a(n) = 48*n*(n-1)/2 + n.at n=31A261343
• Number of permutations f of {1,...,n} such that 3^k + 3^(f(k)) - 1 is prime for every k = 1,...,n.at n=16A321766
• Numbers m such that beta(m) = tau(m)/2 + 1 where beta(m) is the number of Brazilian representations of m and tau(m) is the number of divisors of m.at n=40A326381