291600

Appears in sequences

• Squares of even heptagonal numbers.at n=7A014792
• Sigma(n) / d(n) is a perfect square associated with A049226.at n=36A049227
• Consider the solutions to k = a+b = x*y and a*b = k*(x+y) where k, a, b, x, and y are all positive integers, ordered by increasing k and, in case of ties, by increasing x. Sequence gives values of a*b.at n=19A057421
• Numbers k such that the numerator of Sum_{d|k} 1/d > 3*k.at n=18A069096
• Denominators of the triangle of coefficients T(n,k), read by rows, that satisfy: y^x = Sum_{n=0..x} R_n(y)*x^n for all nonnegative integers x, y, where R_n(y) = Sum_{k=0..n} T(n,k)*y^k and T(n,k) = A107045(n,k)/a(n,k).at n=24A107046
• a(1)=1; at n>=2, a(n) = least square > a(n-1) such that sum a(1)+...+a(n) is a prime number.at n=26A139033
• Triangle read by rows: T(n,m) = (binomial(n - 1, m - 1)*binomial(n, m - 1)/m)^2.at n=47A174158
• Triangle read by rows: T(n,m) = (binomial(n - 1, m - 1)*binomial(n, m - 1)/m)^2.at n=52A174158
• Square array read by antidiagonals: a(p,n) is the number of inversions in all p-ary words of length n on {0,1,2,...,p-1} (p>=2, n>=2).at n=40A181372
• Number of 4 X n 0..1 arrays avoiding 0 0 1 and 0 1 1 horizontally and 0 0 1 and 1 0 0 vertically.at n=13A207753
• Discriminants of the polynomials T_n(x) = Product_{k=0..n} (x - k*(k + 1)/2).at n=3A271386
• Numbers n such that phi(sigma(n))/n > phi(sigma(m))/m for all m < n, where sigma is the sum of divisors function (A000203) and phi is Euler's totient function (A000010).at n=10A293708
• The first of three consecutive squares the sum of which is equal to the sum of three consecutive primes.at n=20A298222
• Numbers k such that sigma(k) - 3k is prime.at n=5A306492
• Squares whose arithmetic mean of digits is 3 (i.e., the sum of digits is 3 times the number of digits).at n=29A316483
• a(1) = 1, and for n > 1, a(n) = A276086(n) * a(A064989(n)).at n=10A324889
• Primorial deflation of A330687 (record positions in A050377): a(n) is the unique integer x such that A108951(x) = A330687(n).at n=34A330689
• Squares that are divisible by both the sum of their digits and the product of their nonzero digits.at n=32A339999
• Positions of records in A116488.at n=32A342869
• Squares that are divisible by the product of their nonzero digits.at n=39A346537