26039

Appears in sequences

• Number of symmetric plane partitions of n.at n=39A005987
• a(n) = 1*prime(n) + 2*prime(n-1) + ... + k*prime(n+1-k), where k=floor((n+1)/2) and prime(n) is the n-th prime.at n=41A023870
• a(n) = s(1)t(n) + s(2)t(n-1) + ... + s(k)t(n-k+1), where k = [ n/2 ], s = (natural numbers), t = (primes).at n=40A024867
• Numbers n such that sigma (phi ( n ) ) = sigma (sigma (n ) ) where phi is Euler's totient and sigma is the multiplicative sum-of-divisors function.at n=13A065556
• Reverse of smallest prime factor of k = largest prime factor of k+1; a(1)=1.at n=22A071392
• Numbers n such that 2*n*k(n) is rational but not an integer, where k(n) is sum of successive remainders when computing the Euclidean algorithm for (1, 1/sqrt(n)) as defined in A086378 (MuPAD program is given there); numbers belonging to A086378 but not to A088900.at n=18A087414
• a(n) = n^3 - (n+1)^2.at n=30A153257
• Number of partitions of n such that (greatest part) - (least part) > number of parts.at n=42A237833
• Triangle read by rows: T(n,k) is the number of n-tuples with sum k + n whose i-th element is a positive integer <= prime(i), 0 <= k < A070826(n).at n=69A239738
• Number of (n+2) X (7+2) 0..1 arrays with no 3 x 3 subblock diagonal sum 0 and no antidiagonal sum 3 and no row sum 1 and no column sum 1.at n=20A257446
• Number of 7 X n 0..1 arrays with no element equal to more than two of its horizontal, diagonal or antidiagonal neighbors and with new values introduced in order 0 sequentially upwards.at n=14A281475