19647

Appears in sequences

• Smallest of 4 consecutive numbers each divisible by a square.at n=30A070284
• Sums of terms of groups in A075621.at n=33A075625
• Integers n such that 10^n-57 is prime.at n=19A108493
• Row sums of triangle A120072 (numerator triangle for H atom spectrum).at n=33A120074
• Numbers k such that 10*(10^(k+1) + 10^k - 1) + 7 is prime.at n=21A123368
• a(n) = 3^n - n*(n-1)/2.at n=9A182453
• Number of nondecreasing arrangements of n+2 numbers in 0..4 with each number being the sum mod 5 of two others.at n=21A183907
• Monotonic ordering of nonnegative differences 3^i-6^j, for 40>= i>=0, j>=0.at n=31A192151
• a(n) = n*(14*n + 13).at n=37A195028
• a(n) = (n - 1)*(n - 2)*(5*n^4 + 3*n^3 + 34*n^2 - 264*n + 180)/360.at n=11A238108
• a(n) = 2*A090495(n) - 1.at n=36A274297
• Composite numbers n such that the sum of proper divisors of n divides 2^n+1.at n=13A278337
• a(n) = (n^3 + 6*n^2 + 17*n + 6)/6.at n=47A341209
• G.f. satisfies A(x) = 1/(1 - 3*x) - x*A(x)^3.at n=11A364645
• Starts of runs of 3 consecutive integers whose exponent of least prime factor in their prime factorization is even.at n=37A365871