31850

Appears in sequences

• a(n) = a(n-1) + a(n-2) + 1 for n>1, a(0)=0, a(1)=1.at n=19A022311
• Number of ways to partition n elements into pie slices of different sizes other than one.at n=42A032155
• Main diagonal of table A083047.at n=14A083048
• Fifth diagonal (m=4) of triangle A084938; a(n) = A084938(n+4,n) = (n^4 + 18*n^3 + 131*n^2 + 426*n)/24.at n=25A090386
• Numbers n such that (2^p + 1)/3 is prime, where p is the n-th prime.at n=38A123176
• a(n)=If[IntegerQ[((3*n - 2)/( n + 1))*a(n - 1)], ((3*n - 2)/(n + 1))* a(n - 1), If[IntegerQ[((4*n - 2)/(n + 1))*a( n - 1)], ((4*n - 2)/(n + 1))*a(n - 1), n*a(n - 1)]].at n=11A155580
• Principal diagonal of the convolution array A213819.at n=24A213820
• Number of 3 X n 0..1 arrays with rows nondecreasing and antidiagonals unimodal.at n=34A224134
• a(n) = 26*n^2.at n=35A244633
• Expansion of r(q)^5 / r(q^5) in powers of q where r() is the Rogers-Ramanujan continued fraction.at n=27A285630
• a(n) = [x^n] Product_{k>=1} (1 + n^(k-1)*x^k) / (1 - n^(k-1)*x^k).at n=6A346452
• Number of positive integers with n digits that are the product of two integers greater than 1 and ending with 1.at n=5A346509
• Starts of runs of 3 consecutive numbers that have an equal number of even and odd exponents in their prime factorization (A187039).at n=15A348077
• Starts of runs of 3 consecutive numbers that have an equal number of unitary and nonunitary prime divisors (A348097).at n=28A348099
• Sum of those numbers t which have a unique representation as the sum of floor(n/2) distinct squares from among 1^2,...,n^2.at n=11A374510