20007

Appears in sequences

• Numbers k such that binomial(2k,k) is not divisible by 3, 5 or 7.at n=12A030979
• Numbers k that divide 7^k + 2^k.at n=38A045580
• Multiples of 9 in which there is no common digit in successive terms.at n=27A083497
• List the positions of all digits '1' in the sequence. This is the lexicographically earliest increasing sequence with this property.at n=45A098645
• Integers that do not appear in A103502.at n=9A103504
• Numbers k such that 3 and 5 do not divide binomial(2*k, k).at n=44A129508
• Expansion of f(-x, -x^5) * f(-x^6) / f(-x)^2 in powers of x where f(, ) and f() are Ramanujan theta functions.at n=26A132302
• Expansion of q^(-2/3) * (psi(-q^3) / psi(-q)^3) * (c(q^2) / 3) in powers of q where psi() is a Ramanujan theta function and c() is a cubic AGM theta function.at n=17A132978
• G.f. satisfies: A(x/A(x)^2) = 1 + x*A(x).at n=6A145350
• Number of partitions of n having no parts with multiplicity 7.at n=37A184642
• Number of partitions p of n such that (number of even numbers in p) = (number of odd numbers in p).at n=45A241638
• Numbers n dividing every cyclic permutation of n^4.at n=26A242740
• Expansion of f(x, x^5) * f(-x^6) / f(x)^2 in powers of x where f() is a Ramanujan theta function.at n=26A254346
• If n mod 3 = 0 then a(n) = 3^(n/3) + 12*n, if n mod 3 = 1 then a(n) = 4*3^((n-4)/3) + 12*n + 51, otherwise a(n) = 2*3^((n-2)/3) + 12*n - 36.at n=24A276401
• Number of minimal edge covers in the n-Moebius ladder.at n=9A290470
• Square spiral on a 2D square lattice, one term per cell, starting at the origin with 0; the integers forming a square of size k X k, for all k = 1, 2, 3, ..., add up to a number that does not contain the digit 1.at n=62A333993
• a(n) is the total number of down steps between the (n-1)-th and n-th up steps in all 2-Dyck paths of length 3*n. A 2-Dyck path is a nonnegative path with steps (1, 2), (1, -1) that starts and ends at y = 0.at n=7A334976
• Numbers that are the sum of four third powers in six or more ways.at n=25A345148
• Numbers that are the sum of four third powers in exactly six ways.at n=22A345149
• Fibonacci sequence beginning 11, 26.at n=15A354383