707584

Appears in sequences

• Number of alternating permutations of order n.at n=11A001250
• E.g.f.: -log(cos(x)*cos(x)) (even powers only).at n=6A012509
• -log(cosh(x)*cos(x))=-4/4!*x^4-544/8!*x^8-707584/12!*x^12...at n=2A012770
• E.g.f.: exp(tan(x)-tanh(x))=1+4/3!*x^3+160/6!*x^6+544/7!*x^7+17920/9!*x^9...at n=11A013451
• sin(tan(x)-tanh(x))=4/3!*x^3+544/7!*x^7-17920/9!*x^9+707584/11!*x^11...at n=4A013452
• tan(tan(x)-tanh(x))=4/3!*x^3+544/7!*x^7+35840/9!*x^9+707584/11!*x^11...at n=5A013453
• T(n,k) = number of permutations of {1..n} with fewer than k interior elements having values lying between the values of their neighbors.at n=65A226441
• Number of arrays of length n that are sums of 2 consecutive elements of length n+1 permutations of 0..n, and no two consecutive rises or falls in the latter permutation.at n=9A229712
• Triangle of Poupard numbers g_n(k) read by rows, n>=1, 1<=k<=2n-1.at n=37A236934
• Triangle of Poupard numbers g_n(k) read by rows, n>=1, 1<=k<=2n-1.at n=47A236934
• Twice the Euler or up/down numbers A000111.at n=11A260786
• Expansion of e.g.f.: sec(x) + 2*tan(x).at n=11A309845
• a(n) = E2_{n}(0) with E2_{n} the polynomials defined in A326480.at n=11A326481
• a(n) = (2*n)!*Pi^(-2*n)*PolyLog(2*n, 1)*Clausen(2*n - 1)/2, where Clausen(n) = A160014(n, 1).at n=5A345365