-239

Appears in sequences

• sech(tan(sinh(x)))=1-1/2!*x^2-7/4!*x^4-73/6!*x^6-239/8!*x^8...at n=4A012158
• a(n) = Sum_{i=n-4..n-1} (-1)^i*a(i), a(1)=1, a(2)=1, a(3)=1, a(4)=1.at n=48A051793
• a(n) = Sum_{i=n-4..n-1} (-1)^i*a(i), a(1)=1, a(2)=1, a(3)=1, a(4)=1.at n=53A051793
• a(n) = Sum_{i=n-6..n-1} (-1)^i * a(i), a(1)=1, a(2)=1, a(3)=1, a(4)=1, a(5)=1, a(6)=1.at n=66A051794
• a(n) = Sum_{i=n-6..n-1} (-1)^i * a(i), a(1)=1, a(2)=1, a(3)=1, a(4)=1, a(5)=1, a(6)=1.at n=73A051794
• Signed distance of primes from LCM(1,...,x) being closest to it. Arguments x were selected from A000961 (powers of primes including primes) in order to use distinct values of LCM exactly once. When both closest primes are in the same distance, then negative were used.at n=59A058030
• a(n+1) = a(n) - a(floor(n/2)), with a(0)=0, a(1)=1.at n=42A062187
• A measure of how close the golden ratio is to rational numbers.at n=44A066212
• Real part of (5 + 12i)^n.at n=4A067359
• Alternating sum sigma(1)-sigma(2)+sigma(3)-sigma(4)+...+((-1)^(n+1))*sigma(n).at n=31A068762
• Signed primes: if prime(n) even, a(n) = 0; if prime(n) == 1 (mod 4), a(n) = prime(n); if prime(n) == -1 (mod 4), a(n) = -prime(n).at n=51A073579
• Array T(r,c) read by antidiagonals: values of triangle A098493 interpreted as polynomials, r >= 0.at n=58A098495
• Diagonal sums of the Fibonacci related number triangle A110314.at n=30A110315
• Row sums of a number triangle related to the Pell numbers.at n=15A110331
• Diagonal sums of number a triangle related to the Pell numbers.at n=30A110332
• Triangle T, read by rows, such that the m-th matrix power satisfies T^m = I + m*(T - I) and consequently the matrix logarithm satisfies log(T) = T - I, where I is the identity matrix.at n=82A112555
• Real part of (2 + 3i)^n.at n=8A121621
• Real part of (3 + 2i)^n.at n=8A121622
• Triangle read by rows, 0 <= k <= n: T(n,k) is the coefficient of x^k in the characteristic polynomial of I + A^(-1), where A is the n-step Fibonacci companion matrix and I is the identity matrix.at n=73A122771
• a(n) = -2*a(n-1) + a(n-2) for n>1, a(0)=1, a(1)=-1.at n=7A123335