25744

Appears in sequences

• Interprimes which are of the form s*prime, s=16.at n=21A075291
• a(n) = Sum_{j=0..n} A000293(j).at n=12A143123
• Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, 0), (0, 1, -1), (0, 1, 1), (1, 0, 0)}.at n=9A149945
• Number of cyclotomic cosets of 9 mod 10^n.at n=40A220020
• Equals two maps: number of nX2 binary arrays indicating the locations of corresponding elements equal to exactly two of their king-move neighbors in a random 0..3 nX2 array.at n=7A220339
• T(n,k)=Equals two maps: number of nXk binary arrays indicating the locations of corresponding elements equal to exactly two of their king-move neighbors in a random 0..3 nXk array.at n=37A220342
• O.g.f.: exp( Sum_{n>=1} (sigma(2*n)^2 - sigma(n)^2) * x^n/n ).at n=6A227732
• Numbers n such that the decimal expansions of both n and n^2 have 2 as smallest digit and 7 as largest digit.at n=10A257123
• Expansion of Product_{k>=1} 1/(1 - (2^k + 1) * x^k).at n=8A322199
• For any n > 0, let E_n be the variant of Van Eck's sequence where values are taken mod n; if E_n is eventually periodic, then a(n) is the length of its transient part; otherwise a(n) = -1.at n=41A352641
• Column 1 of triangle A370041.at n=38A370154
• Expansion of (1 + x)/(1 - x^3*(1 + x)^4).at n=19A375320