20712

Appears in sequences

• Sum of 12 nonzero 8th powers.at n=40A003390
• Numbers that are the sum of 8 positive 9th powers.at n=11A003397
• a(n) = prime(n)*prime(n-1) + 1.at n=34A023523
• Numbers k such that sigma(k+1) divides sigma(k), where sigma(k) is the sum of positive divisors of k.at n=30A058073
• Numbers k such that gcd(sigma(k), sigma(k+1)) > k.at n=41A066025
• Sum of terms in n-th row of A077164.at n=27A077167
• Natural number transform of Aitken's triangle.at n=33A127740
• Number of permutations of floor(i*7/6), i=0..n-1, with all sums of 3 adjacent terms unique.at n=7A152324
• Number of 8X8 arrays of squares of integers, symmetric under 90 degree rotation, with all rows summing to n.at n=19A156397
• a(n) = 36*n^2 - n.at n=23A157286
• a(n) = 1728*n - 24.at n=11A157287
• a(n) = 144*n^2 - 2*n.at n=11A158135
• a(n) = Sum_{i=1..Fibonacci(n)} sigma_0(i) where sigma_0(n) is A000005(n).at n=17A158568
• a(n) = 576*n^2 - 24.at n=5A158636
• Numbers k such that sigma(k) = 2*sigma(k+1).at n=15A163193
• Number of partitions of n containing a clique of size 1.at n=37A183558
• Expansion of q / (chi(q) * chi(q^2) * chi(q^3) * chi(q^6))^2 in powers of q where chi() is a Ramanujan theta function.at n=34A212770
• Numbers k such that the average of the divisors of k and k+1 is the same.at n=12A238380
• a(n) = n^4 - 2n.at n=12A246767
• Terms of A143407, sorted.at n=42A270564