22971

Appears in sequences

• Numbers k such that the Woodall number k*2^k - 1 is prime.at n=21A002234
• Cycle class sequence c(n) (the number of true cycles of length n in which a certain node is included) for zeolite NON = Nonasil-[ 4158 ] [Si88O176].4R starting with a T2 atom.at n=13A019210
• Number of partitions of n with equal number of parts congruent to each of 0 and 2 (mod 5).at n=48A035553
• Number of singular points on n-th order Chmutov surface.at n=38A057870
• Expansion of (1+2x^2)/(1-x-4x^5).at n=22A098524
• Number of nX5 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 2,0,3,1,4 for x=0,1,2,3,4.at n=5A196284
• Number of nX6 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 2,0,3,1,4 for x=0,1,2,3,4.at n=4A196285
• T(n,k)=Number of nXk 0..4 arrays with each element x equal to the number of its horizontal and vertical neighbors equal to 2,0,3,1,4 for x=0,1,2,3,4.at n=49A196287
• T(n,k)=Number of nXk 0..4 arrays with each element x equal to the number of its horizontal and vertical neighbors equal to 2,0,3,1,4 for x=0,1,2,3,4.at n=50A196287
• Number of 3 X n 0..1 arrays with rows unimodal and antidiagonals nondecreasing.at n=12A224410
• Number of n X 4 0..3 arrays with no element x(i,j) adjacent to value 3-x(i,j) horizontally, diagonally or antidiagonally, and top left element zero.at n=2A232951
• T(n,k)=Number of nXk 0..3 arrays with no element x(i,j) adjacent to value 3-x(i,j) horizontally, diagonally or antidiagonally, and top left element zero.at n=17A232955
• Number of 3 X n 0..3 arrays with no element x(i,j) adjacent to value 3-x(i,j) horizontally, diagonally or antidiagonally, and top left element zero.at n=3A232957
• Numbers k such that card({x|sigma(x)=k}) > 1 and (Sum_{sigma(x)=k} x) < k.at n=26A258931
• Numbers n such that 3*n and n^3 have the same digit sum.at n=36A260906
• Odd numbers m such that sigma(x) = m has more than 1 solution.at n=12A300869
• a(n) = (n^4 + 5*n^3 + 11*n^2 + 7*n)/6.at n=18A332697
• Sum of the odd divisors of the primorial inflation of n.at n=48A337204
• Irregular triangle read by rows: T(n,k), n > 1 and k <= n, is the smallest composite number x whose set of digits and the set of digits in all prime factors of x, when written in base n, contain exactly k digits in common, or -1 if no such number exists.at n=31A374225
• Square array A(n, k) = sigma((2n-1)^2) * sigma((2k-1)^2), read by antidiagonals.at n=58A379220