18529

Appears in sequences

• Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 100 ones.at n=7A031868
• a(n) = (p^2 - p + 2)/2 for p = prime(n); number of squares modulo p^2.at n=43A072205
• Sum of terms in n-th row of A077164.at n=26A077167
• (2n+1)-digit anti-palindromic numbers or numberdromes, whose first and last digits add to ten, second and next-to-last add to ten and so on with the central digit a 5.at n=16A093472
• Least j > 1 such that j^2 = (4*n^2 + 2)*(k^2) + (4*n^2 + 2)*k + 1.at n=16A106231
• Odd integers that do not generate monotonically decreasing infinitary aliquot sequences.at n=37A127667
• Number of n X n binary arrays symmetric under horizontal reflection with all ones connected only in a 10101-11111 pattern in any orientation.at n=10A147422
• 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, 0), (-1, 0, 0), (-1, 1, -1), (-1, 1, 1), (1, 0, 0)}.at n=10A148531
• Maximum number of partitions of n into exactly k parts, each <= k. a(n) is maximum in each row of A157044.at n=54A157046
• Number of arrays of -1..1 integers x(1..n) with every x(i) in a subsequence of length 1 or 2 with sum zero.at n=12A193641
• Number of labeled rooted trees with n nodes with every leaf at the same height.at n=6A238372
• Numbers n such that the digit sum of Fibonacci(n) is equal to the digit sum of Lucas(n).at n=37A244923
• Numbers k such that A084937(3k) > A084937(3k+1).at n=39A249689
• Those terms of A255571 whose every A080541/A080542-rotation is also a term of A255571.at n=28A258001
• Numbers k such that k!!! - 3^k is prime.at n=28A261316
• a(n) = sqrt(A370259(2*n+1)).at n=4A370260