28008

Appears in sequences

• a(1) = 1+2-3 = 0, a(2) = 4+5+6-7 = 8, a(3) = 8+9+10+11-12 = 26, a(4) = 13+14+15+16+17-18 = 57, ...at n=36A111694
• Number of lines through at least 2 points of a 9 X n grid of points.at n=39A160849
• Sum of the numerators for computing the second moment of the probability mass function (PMF) of the number of 2-cycles in the involutions on n elements (A000085) assuming the involutions are all equally likely.at n=8A174764
• Number of 0..n arrays x(0..8) of 9 elements with zero 6th differences.at n=18A200276
• Consecutive states of the linear congruential pseudo-random number generator 172*s mod 30307 when started at s=1.at n=25A385032
• Numbers k such that the powerful part of the sum of divisors of k (A387726) is greater than or equal to k, and sigma(k) is not itself a powerful number.at n=25A387729