18051

Appears in sequences

• Solutions to A096509[x]=6; number of prime-powers [including primes] in the neighborhood of x with Ceiling[Log[x]] radius equals 6.at n=14A096517
• a(n) = 50*n^2 + 1.at n=18A157916
• Number of -2..2 arrays of n elements with first, second and third differences also in -2..2.at n=9A202118
• The number of skew sum indecomposable permutations which avoid the patterns 3124 and 4312.at n=8A228771
• Numerators of coefficients in Taylor series expansion of sqrt(m(x)) where m(x) is g.f. for Motzkin numbers A001006.at n=6A261421
• a(n) = Sum of (Y(2,p)^2) over the partitions p of n, Y(2,p) = number of part sizes with multiplicity 2 or greater in p.at n=29A302347
• a(1) = 13; for n > 1, if a(n-1) is even, then a(n) = a(n-1)/2; otherwise, a(n) = a(n-1) + prime(a(n-1)).at n=20A358166
• Number of distinct regions among all circles that can be constructed on vertices of an n-sided regular polygon, using only a compass.at n=18A359046