235620

Appears in sequences

• a(n) = n*(n+1)*(n+2)*(n+3)/6.at n=33A033488
• Ordered products of the sides of primitive Pythagorean triangles.at n=15A063011
• Numbers k such that phi(k) < k/5.at n=30A066765
• Denominators of expansion of 1/x+1/log(1-x).at n=32A075178
• LCM of terms in periodic part of continued fraction expansion of square root of 1+2^n.at n=10A077632
• Largest element of n-th row of A080738.at n=22A080742
• Heptagorials: n-th polygorial for k=7.at n=5A084940
• Values of y in x^2 - 289 = 2*y^2.at n=17A106528
• Binet's factorial series. Denominators of the coefficients of a convergent series for the logarithm of the Gamma function.at n=31A122253
• Triangle T(n, k) = (binomial(n,2))! / (k! * abs(k+1 - binomial(n,2))!), read by rows.at n=39A123146
• Smallest number having exactly n triangular divisors.at n=22A130317
• Numbers with prime factorization pqrst^2u^2.at n=1A190380
• Numbers k such that Euler phi(Dedekind psi(k)) > k.at n=17A196200
• Numbers k such that both k and k^2 are sums of a twin prime pair.at n=32A213784
• a(n) = lcm(A000793(n),p1,p2,...,pk) for such a partition {p1+p2+...+pk} of n that maximizes this value among all partitions of n.at n=27A225627
• a(n) = 4*a(n-4) + 6*a(n-8) + 4*a(n-12) + a(n-16) for n>15, with the sixteen initial values as shown.at n=33A238188
• Numbers n having a proper divisor d such that sigma(n) - k*d = k*n. Case k = 4.at n=21A291458
• a(n) = Product_{d|n, d<n} A019565(A003714(d)), where A003714(n) is the n-th Fibbinary number.at n=49A300834
• Primitive 4-abundant numbers: Numbers k such that sigma(k) > 4k (A068404) all of whose proper divisors d are 4-deficient numbers (having sigma(d) < 4d).at n=18A307114
• Primitive terms of A023198: numbers k with the property sigma(k)/k >= 4 that are not divisible by any other number with that property.at n=20A392936