22405

Appears in sequences

• Numbers n such that n divides the (right) concatenation of all numbers <= n written in base 19 (most significant digit on right).at n=28A029512
• Numbers k such that 3k-4, 3k-2, 3k+2, and 3k+4 are primes.at n=28A173092
• Number of symmetry classes of 3 X 3 magilatin squares with positive values < n.at n=20A173729
• Number of (n+2)X(4+2) 0..1 arrays with each 3X3 subblock having clockwise perimeter pattern 00000001 00000011 or 00001011.at n=6A260497
• Number of (n+2)X(7+2) 0..1 arrays with each 3X3 subblock having clockwise perimeter pattern 00000001 00000011 or 00001011.at n=3A260500
• a(n) = binomial(2*n,n) - ceiling(2^(2*n)/(n+1)).at n=9A282708
• Number of nX6 0..1 arrays with every element unequal to 0, 1, 2 or 7 king-move adjacent elements, with upper left element zero.at n=9A304228
• Squarefree semiprimes k such that k+1 is the product of three distinct primes and k+2 is the product of four distinct primes.at n=30A376352
• G.f. A(x) satisfies A(x) = (1 + x) * C(x*A(x)), where C(x) is the g.f. of A000108.at n=7A381787