25199

Appears in sequences

• -arctan(sin(x)-arctanh(x))=3/3!*x^3+23/5!*x^5+721/7!*x^7+25199/9!*x^9...at n=4A013391
• Composite numbers n such that k! == 1 (mod n) for some k > 2.at n=25A049048
• Numbers n such that sigma(phi(n))/sigma(n) = 3.at n=7A067383
• Least m which can be written as i*j+i+j in n different ways: A072670(m)=n.at n=44A072671
• a(n) is the unique odd positive solution y of 2^n = 7x^2 + y^2.at n=27A077021
• Brilliant numbers k such that 2k+1 is also brilliant.at n=13A085649
• Numbers k such that either k or k+1 is divisible by the numbers from 1 to 10.at n=38A131663
• Composites c where |c-m| = 1, where m is any of the smallest positive integers with their number of divisors. (m belongs to sequence A007416.)at n=44A152246
• a(n) = 900*n - 1.at n=27A158409
• a(n) = 28*n^2 - 1.at n=29A158554
• Numbers m such that m mod k is k-1 for all k = 2..9.at n=9A166931
• a(n) = 5*n! - 1.at n=7A173317
• a(1)=1. a(n) = the smallest integer > a(n-1) such that d(a(n))+d(a(n)+1) > d(a(n-1))+d(a(n-1)+1), where d(m) = the number of divisors of m.at n=39A175143
• Numbers k for which d(k-1) + d(k+1) is a record, where d(k) is the number of divisors of k.at n=34A189828
• Smallest number requiring n terms to be expressed as a sum of factorials.at n=25A200748
• a(n) = n^3 - 2*n^2 - 1.at n=29A214731
• Lucas pseudoprimes.at n=22A217120
• Strong Lucas pseudoprimes.at n=7A217255
• Numbers of the form p*q, p and q prime with q=2p-3.at n=18A226755
• Numbers decremented by their digit product produce a cube.at n=35A229184