22387

Appears in sequences

• Generalized Pellian with second term equal to 9.at n=10A048696
• Triangle T(n, k, m) = (m*(n-k) + 1)*T(n-1, k-1, m) + (m*k + 1)*T(n-1, k, m) + m*f(n,k)*T(n-2, k-1, m) with T(n, 0, m) = T(n, n, m) = 1, f(n, k) = 2*k if k <= floor(n/2) otherwise 2*(n-k), and m = 2, read by rows.at n=23A157277
• Triangle T(n, k, m) = (m*(n-k) + 1)*T(n-1, k-1, m) + (m*k + 1)*T(n-1, k, m) + m*f(n,k)*T(n-2, k-1, m) with T(n, 0, m) = T(n, n, m) = 1, f(n, k) = 2*k if k <= floor(n/2) otherwise 2*(n-k), and m = 2, read by rows.at n=25A157277
• a(n) = ((1+4*sqrt(2))*(3+2*sqrt(2))^n + (1-4*sqrt(2))*(3-2*sqrt(2))^n)/2.at n=5A164604
• Primitive numbers in A229306.at n=39A229310
• Number of nX6 0..2 arrays with every 0 next to a 1 and every 1 next to a 2 horizontally or antidiagonally.at n=1A232293
• T(n,k)=Number of nXk 0..2 arrays with every 0 next to a 1 and every 1 next to a 2 horizontally or antidiagonally.at n=22A232295
• Number of 2Xn 0..2 arrays with every 0 next to a 1 and every 1 next to a 2 horizontally or antidiagonally.at n=5A232296
• Semiprimes of the form S(n) + T(n) where S(n) and T(n) are the n-th square and the n-th triangular numbers.at n=19A240914
• Least number x such that x^n has n digits equal to k. Case k = 9.at n=19A285456