100215

Appears in sequences

• Smallest k whose 'Reverse and Subtract' trajectory has a preperiodic part of length n.at n=31A072138
• Starting term of the smallest n-chain of numbers whose squares are permutations of the same digits.at n=35A085546
• Least number that requires n steps to reach 0 by repeated application of f: x -> abs(x - reverse(x)).at n=31A109891
• (k^2)-th k-smooth number for k = prime(n).at n=36A133581
• Number of nX7 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 0 0 and 1 0 1 vertically.at n=3A208038
• T(n,k)=Number of nXk 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 0 0 and 1 0 1 vertically.at n=48A208039
• Number of 4 X n 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 0 0 and 1 0 1 vertically.at n=6A208040
• Odd numbers that are not of the form p + 2^a + 2^b with b > a > 0, and p prime.at n=14A268693
• Numbers k such that 477*2^k+1 is prime.at n=42A319487