23762

Appears in sequences

• Numbers k such that the continued fraction for sqrt(k) has odd period and if the last term of the periodic part is deleted then there are a pair of central terms both equal to 9.at n=36A031422
• Least of four consecutive numbers which are cubefree and not squarefree, i.e., numbers k such that {k, k+1, k+2, k+3} are in A067259.at n=10A071320
• a(n) = 2*prime(n)^2.at n=28A079704
• Smaller of two consecutive numbers with the same prime signature not occurring earlier.at n=14A091405
• a(n) = 3*L(2*n)/5 - (-1)^n/5, where L = A000032.at n=11A099016
• Numbers k such that k * phi(k) is a cube.at n=32A114076
• X-values of solutions to the equation X*(X + 1) - 6*Y^2 = 0.at n=5A132596
• Numbers n, satisfying A055231(n+1) - A055231(n) = 1, and with n and n+1 not squarefree.at n=3A140394
• 2*p^2, for p an odd prime.at n=27A143928
• a(n) = -cos((2*n-1)*arcsin(sqrt(3)))^2 = -1 + cosh((2*n-1)*arcsinh(sqrt(2)))^2.at n=2A146312
• a(n) = - sin^2((2n-1)*arccos(sqrt n)) = sin^2((2n-1)*arcsin(sqrt n)) - 1.at n=3A173171
• Expansion of 1/(1 - x - x^9 - x^17 + x^18).at n=56A175772
• Number of 7-step S, E, and NW-moving king's tours on an n X n board summed over all starting positions.at n=11A187512
• Numbers k such that core(k+1) = core(k)+1 and k is not squarefree, where core(k) = A007913(k).at n=6A260198
• Numbers k such that k and k^2 are the sums of two nonzero squares in exactly two ways.at n=41A273293
• a(n) = a(n-1) + a(n-3) + a(n-4), where a(0) = 0, a(1) = 1, a(2) = 0, a(3) = 2.at n=23A295681
• a(n) = a(n-1) + a(n-3) + a(n-4), where a(0) = 1, a(1) = 2, a(2) = 2, a(3) = 1.at n=22A295687
• Square array A(n,k), n >= 0, k >= 0, read by antidiagonals, where A(n,k) is 1/2 * (-1 + Sum_{j=0..k} binomial(2*k,2*j)*(n+1)^(k-j)*n^j).at n=30A322699
• a(n) = n * (16*n^2+20*n+5)^2.at n=2A322745
• Numbers k such that A063659(k) = A063659(k+1).at n=4A336673