380380

Appears in sequences

• Numerators of expansion of (1-x)^(-1/3).at n=10A004117
• Area ar/6 (divided by 6) of primitive Pythagorean triangles such that perimeters are Averages of twin prime pairs, q=p+1, a=q^2-p^2, c=q^2+p^2, b=2*p*q, ar=a*b/2; s=a+b+c, s-+1 are primes.at n=13A155177
• Numbers k such that the sum of the distinct prime divisors of k equals three times the largest prime divisor of k.at n=32A200090
• Number T(n,k) of 2n-length strings of balanced parentheses of exactly k different types that are introduced in ascending order; triangle T(n,k), n>=0, 0<=k<=n, read by rows.at n=42A253180
• Number of 2n-length strings of balanced parentheses of exactly 6 different types that are introduced in ascending order.at n=2A258394
• a(n) = binomial(n+3, 3)*(1 + binomial(n+2, 3)/4).at n=18A291288
• Unitary abundant numbers k such that k+2 is also unitary abundant.at n=11A292704
• a(n) is the smallest square pyramidal number divisible by exactly n square pyramidal numbers.at n=9A359094