21889

Appears in sequences

• exp(arcsinh(x)*exp(x))=1+x+3/2!*x^2+9/3!*x^3+33/4!*x^4+145/5!*x^5...at n=8A012584
• a(n) = 15*n^2 + 6*n + 1.at n=38A080861
• G.f.: x*(1+x+x^2)*(1+6*x+8*x^2+4*x^3-x^4)/((1+x)^2*(1-x)^4).at n=22A147691
• Expansion of (1+x+x^2) / ((1-x)*(1-x-x^2)).at n=18A154691
• a(n) = 38*n^2 + 1.at n=24A158593
• Digit sums of A092571.at n=19A165724
• Number of representations of n as a sum of products of pairs of positive integers, considered to be equivalent when terms or factors are reordered.at n=30A182269
• Numbers n such that 2*n + {3, 5, 9, 11} are all primes.at n=24A222960
• Numbers k such that k!4 + 2^4 is prime, where k!4 = k!!!! is the quadruple factorial number (A007662).at n=35A291344
• Number of n X 2 0..1 arrays with each 1 adjacent to 1 or 2 king-move neighboring 1s.at n=8A295841
• T(n,k)=Number of nXk 0..1 arrays with each 1 adjacent to 1 or 2 king-move neighboring 1s.at n=46A295847
• Smallest m such that prime(3*n)# can be written as a product of n sphenic numbers each <= m.at n=7A337494