26610

Appears in sequences

• Absolute value of Glaisher's alpha(n).at n=30A002290
• n satisfying sigma(n+1) = sigma(n-1).at n=31A055574
• a(n) = (2*n - 1)*(7*n^2 - 7*n + 6)/6.at n=22A063490
• Numbers k such that sigma(k-1) divides sigma(k+1).at n=37A067130
• Numbers n such that sigma(n+1) - sigma(n-1) = k*n for some integer k, where sigma(n) = A000203 (sum of divisors of n).at n=32A223137
• Number of nX7 0..2 arrays with diagonals and antidiagonals unimodal and rows nondecreasing.at n=2A224352
• T(n,k)=Number of nXk 0..2 arrays with diagonals and antidiagonals unimodal and rows nondecreasing.at n=38A224353
• Number of 3 X n 0..2 arrays with diagonals and antidiagonals unimodal and rows nondecreasing.at n=6A224354
• Numbers k such that sigma(k+1) divides sigma(k-1).at n=33A227304
• Number of (n+2)X(1+2) 0..3 arrays with every 3X3 subblock row, column, diagonal and antidiagonal sum not equal to 0 2 5 6 or 7.at n=7A252212
• T(n,k)=Number of (n+2)X(k+2) 0..3 arrays with every 3X3 subblock row, column, diagonal and antidiagonal sum not equal to 0 2 5 6 or 7.at n=28A252219
• T(n,k)=Number of (n+2)X(k+2) 0..3 arrays with every 3X3 subblock row, column, diagonal and antidiagonal sum not equal to 0 2 5 6 or 7.at n=35A252219
• Expansion of Product_{k>=1} 1/(1 - 3*k*x^k).at n=8A265974
• Numbers k such that 7*10^k + 57 is prime.at n=31A270974
• Sum of squares of parts of the partitions of 2n into two squarefree parts.at n=27A280316
• Numbers k whose nearest neighbors have the same number of divisors, the same number of distinct prime factors, and the same sum of divisors.at n=11A294173
• The number of regions inside a concave circular triangle formed by the straight line segments mutually connecting all vertices and all points that divide the sides into n equal parts.at n=15A340685
• Products of four distinct primes between sphenic numbers (products of 3 distinct primes).at n=22A351382