18126

Appears in sequences

• a(n) is the concatenation of n and 7n.at n=17A009441
• Expansion of (eta(q^2) / eta(q))^24 in powers of q.at n=4A014103
• Number of symmetric nonnegative integer 9 X 9 matrices with sum of elements equal to 4*n, under action of dihedral group D_4.at n=7A054549
• Expansion of (eta(q) * eta(q^4) / eta(q^2)^2)^24 in powers of q.at n=4A100130
• Triangle, read by rows, of the coefficients of [x^k] in G100231(x)^n such that the row sums are 5^n-1 for n>0, where G100231(x) is the g.f. of A100231.at n=49A100232
• Integers that are Rhonda numbers to base 15.at n=5A100974
• a(n) = 625*n + 1.at n=28A158383
• Triangle of coefficients of polynomials v(n,x) jointly generated with A209135; see the Formula section.at n=49A209136
• Number of (w,x,y,z) with all terms in {1,...,n} and w*x+y*z<n^2.at n=12A212111
• Initial members of abundant quadruplets, i.e., values of k such that (k, k+2, k+4, k+6) are all abundant numbers.at n=29A231089
• Numbers m such that the decimal digits of m are exactly the same as those of all the indices corresponding to the prime factors of m.at n=14A287916
• Number of nX6 0..1 arrays with every element unequal to 0, 2, 3, 5, 7 or 8 king-move adjacent elements, with upper left element zero.at n=7A316618
• Triangle read by rows: T(n,k) (n >= 5, 4 <= k <= n-1) = number of lattice 3-polytopes of width larger than 1, size n, and k vertices.at n=29A319958
• Column k=8 of triangle A257673.at n=4A321953
• a(n) is the smallest positive integer which can be represented as the sum of distinct nonzero icosahedral numbers in exactly n ways, or -1 if no such integer exists.at n=11A360215