22704

Appears in sequences

• Base 7 digits are, in order, the first n terms of the periodic sequence with initial period 1,2,3.at n=5A037607
• Number of walks of length n along the edges of a dodecahedron between two opposite vertices.at n=12A054883
• Coefficients of a power series whose convolution consists of only the even-indexed terms of the sequence.at n=46A073707
• Coefficients of a power series whose convolution consists of only the even-indexed terms of the sequence.at n=47A073707
• Generating function A(x) satisfies A(x) = (1+x)^2*A(x^2)^2, with A(0)=1.at n=23A073708
• Starting positions of strings of three 3's in the decimal expansion of Pi.at n=11A083610
• a(1) = 1, a(2) = 2; for n >= 2, a(n+1) = a(n) + sum of the unique prime factors of a(n).at n=29A096460
• (1/4)*number of nonsquare rectangles with corners on an n X n grid of points.at n=19A122225
• Numbers k such that Sum_{i=1..k} i^sigma(i) == 0 (mod k).at n=7A227427
• a(n) = (n^7 - 21*n^3 + 20*n)/210.at n=9A239095
• Number of (n+2) X (1+2) 0..1 arrays with every 2 X 2 and 3 X 3 subblock diagonal maximum minus antidiagonal minimum unequal to its neighbors horizontally and vertically.at n=8A253360
• T(n,k)=Number of (n+2)X(k+2) 0..1 arrays with every 2X2 and 3X3 subblock diagonal maximum minus antidiagonal minimum unequal to its neighbors horizontally and vertically.at n=36A253367
• The pi-based arithmetic derivative of n!.at n=7A258845
• Expansion of Product_{k>=1} 1/(1 - x^k)^(k^2*(k+1)/2).at n=9A279216
• Number of nonequivalent dissections of an n-gon into 3 polygons by nonintersecting diagonals rooted at a cell up to rotation.at n=42A295622
• Least k such that p = k^2 + 1 and q = (k+2n)^2 + 1 are prime numbers with q - p square.at n=42A339007
• Number of unordered pairs of natural numbers k1, k2 such that their product is an n-digit number and has the same multiset of digits as in both k1 and k2.at n=7A370676