41400

Appears in sequences

• Molien series for Gamma_3(2).at n=6A027630
• a(n) = A001864(n+1)/2.at n=5A036276
• Composite numbers k such that k!/k# - 1 is prime, where k# = primorial numbers A034386.at n=29A049421
• Triangle T(n,k) = Sum_{i=0..k} (-1)^(i+k)*binomial(k,i)*Sum_{j=0..n} (i+1)^j*(3n-3j+1) read by rows.at n=32A116923
• Nonnegative values x of solutions (x, y) to the Diophantine equation x^2+(x+761)^2 = y^2.at n=8A122694
• a(n) = n*(n - 1)*(27*n^2 - 67*n + 74)*n!/24.at n=4A138783
• Numbers k such that k!/k#-1 is prime, where k# is the primorial function (A034386).at n=34A140293
• Number of n-leaf binary trees that do not contain (((()())())(()(()()))) as a subtree.at n=11A159769
• Numbers with prime factorization p*q^2*r^2*s^3 (where p, q, r, s are distinct primes).at n=13A190109
• a(n) = n^2*(n+1)*(3*n+1)/4.at n=15A213827
• Total number of parts of multiplicity 9 in all partitions of n.at n=49A222709
• Denominator of Sum_{k=1..n} 1/(k(k+1)(k+2)(k+3)) = Sum_{k=1..n} 1/Pochhammer(k,4).at n=22A230340
• a(n) = Sum_{k=0..n} k*A000009(k).at n=29A270105
• Numbers n such that psi(n) is the sum of proper divisors of n where psi(n) = A001615(n).at n=2A291209
• a(n) = [x^n] exp(Sum_{k>=1} x^k*(1 + (n - 3)*x^k)/(k*(1 - x^k)^3)).at n=9A318118
• Number of double cosets of the Sylow 2-subgroup of the symmetric group S_n.at n=13A360808
• Expansion of (1/x) * Series_Reversion( x * (1 - x^2 / (1 - x)^3)^2 ).at n=9A389694