24806

Appears in sequences

• Product of a prime and the following number.at n=36A036690
• Squarefree numbers k with largest prime factor = floor(sqrt(k)).at n=25A071311
• Deficient oblong numbers.at n=27A077804
• Squarefree oblong (pronic) numbers having an odd number of prime factors.at n=21A098827
• a(n) = (4*n+1)*(4*n+2) = (4*n+2)!/(4*n)!.at n=39A157870
• a(n) = 25*n^2 + 25*n + 6.at n=31A177059
• a(n) = (7*n + 3)*(7*n + 4).at n=22A177071
• a(n) = (9*n+4)*(9*n+5).at n=17A177073
• Number of arrangements of n+1 nonzero numbers x(i) in -4..4 with the sum of floor(x(i)/x(i+1)) equal to zero.at n=4A189493
• T(n,k)=Number of arrangements of n+1 nonzero numbers x(i) in -k..k with the sum of floor(x(i)/x(i+1)) equal to zero.at n=32A189498
• Number of arrangements of 6 nonzero numbers x(i) in -n..n with the sum of floor(x(i)/x(i+1)) equal to zero.at n=3A189502
• Consider a number of k digits n = d_(k)*10^(k-1) + d_(k-1)*10^(k-2) + … + d_(2)*10 + d_(1). Sequence lists the numbers n such that phi(n) = Sum_{i=1..k-1}{sigma(Sum_{j=1..i}{d_(j)*10^(j-1)})} (see example below).at n=8A240897
• Irregular table read by rows: T(0,0) = 2 and T(n,2k) = T(n-1,k)+1, T(n,2k+1) = T(n-1,k)*(T(n-1,k)+1) for 0 <= k < 2^(n-1).at n=44A273317
• Alternate version of A273317 with rows sorted in ascending order.at n=54A273338
• Numbers k such that (56*10^k + 223)/9 is prime.at n=22A275524
• a(n) = Sum_{d|n} (n/d)^(d-1) * binomial(d+n-1,n).at n=8A363663
• a(n) is the area of the largest rectangle that can be formed from n sticks whose lengths are 1, 2, ..., n.at n=35A381769