20155392

Appears in sequences

• Numbers that are the sum of 2 positive 9th powers.at n=20A003391
• Numbers that are the sum of at most 2 positive 9th powers.at n=27A004886
• Ratios of successive terms are 2, 3, 2, 3, 2, 3, 2, 3, ...at n=19A026549
• For an integer n with prime factorization p_1*p_2*p_3* ... *p_m let n* = (p_1+1)*(p_2+1)*(p_3+1)* ... *(p_m+1); sequence gives n* such that n* is divisible by n, ordered by increasing value of n.at n=21A064518
• Ninth column of triangle A067425.at n=5A067429
• Triangle with T(n,k)=n!*(k-1)^k/k! where 1<=k<=n.at n=42A076482
• a(n) = 6^n*(n^2 - n + 72)/72.at n=9A081912
• a(n) = phi(6^n).at n=10A167747
• Expansion of 36*x^2*(1+36*x^2-6*x) / ((36*x^2+6*x+1)*(1-6*x)^2).at n=8A181635
• Denominators of reduced coefficients in expansion of e.g.f. for operads for alia algebras.at n=21A220435
• Composite numbers such that Sum_{i=1..k} (1 + 1/p_i) - Product_{i=1..k} (1 + 1/p_i) is an integer, where p_i are the k prime factors of n (with multiplicity).at n=24A226365
• a(n) = 432*n^6.at n=6A228105
• Triangle read by rows: terms T(n,k) of a binomial decomposition of n*(-1)^n as Sum(k=0..n)T(n,k).at n=53A244141
• Triangle read by rows: number of spanning trees obtained for an almost-complete bipartite graph by removing k disjoint edges from the complete bipartite graph K n,n with k<=n.at n=17A260383
• Number of permutations p of [n] such that p(i)-i is a multiple of ten for all i in [n].at n=29A275065
• Records in A319100.at n=33A307252
• Dirichlet g.f.: Product_{k>=2} 1 / (1 - k^(-s))^(k^9).at n=5A343289
• Number of ways to tile a double-hexagon strip of n hexagons, using single and double hexagons.at n=29A354541
• For an integer k with prime factorization p_1*p_2*p_3* ... *p_m let k* = (p_1+1)*(p_2+1)*(p_3+1)* ... *(p_m+1); sequence gives k* such that k* is divisible by k.at n=21A380574
• Numbers of the form P(k)^m * Q(k), m >= 0, with P(k) = Product_{i=1..k} prime(i) = A002110(k) and Q(k) = Product_{j=1..k} P(j) = A006939(k).at n=39A387491