186368

Appears in sequences

• Let sigma_m (n) be result of applying sum-of-divisors function m times to n; call n (m,k)-perfect if sigma_m (n) = k*n; sequence gives the (3,k)-perfect numbers.at n=35A019292
• a(n) = 2^(n-2)*binomial(n+1,2).at n=11A052482
• Expansion of 1/((1+4*x)*(1-12*x)).at n=5A053536
• Factorial splitting: write n! = x*y*z with x<y<z and x maximal and z is minimal; sequence gives value of z.at n=15A061032
• Sequence associated with a(n) = 2*a(n-1) + k*(k+2)*a(n-2).at n=12A080929
• Number of ternary Lyndon words with exactly four 1's.at n=10A124722
• Number of tilings of a 5 X n rectangle using n pentominoes of shapes F, U, N.at n=31A234931
• E.g.f. C(x,y) = 1 + Integral S(x,y)*C(y,x) dx such that C(x,y)^2 - S(x,y)^2 = 1 and C(y,x) = Integral S(y,x)*C(x,y) dy, where C(x,y) = Sum_{n>=0} Sum_{k=0..n} T(n,k) * x^(2*n-2*k)*y^(2*k)/(2*n)!, as a triangle of coefficients T(n,k) read by rows.at n=34A322731
• E.g.f. C(y,x) = 1 + Integral S(y,x)*C(x,y) dy such that C(x,y)^2 - S(x,y)^2 = 1 and C(x,y) = Integral S(x,y)*C(y,x) dx, where C(y,x) = Sum_{n>=0} Sum_{k=0..n} T(n,k) * x^(2*n-2*k)*y^(2*k)/(2*n)!, as a triangle of coefficients T(n,k) read by rows.at n=29A322732
• Triangular array read by rows. Let P be the poset of all even sized subsets of [2n] ordered by inclusion. T(n,k) is the number of intervals in P with length k, 0<=k<=n, n>=0.at n=29A328821
• Positions of records in A116489.at n=35A342868
• Factorial splitting: write n! = x*y*z with x <= y <= z and minimal z-x; sequence gives value of z.at n=18A355191
• Expansion of e.g.f. C(x,k) satisfying C(x,k) = cosh( x*cosh(k*x*C(x,k)) ), as a triangle read by rows.at n=34A370430
• Expansion of e.g.f. D(x,k) satisfying D(x,k) = cosh( k*x*cosh(x*D(x,k)) ), as a triangle read by rows.at n=29A370432
• Expansion of e.g.f. cosh(x)^2*(x+x^2/2).at n=14A385601