22555

Appears in sequences

• Numbers k such that 9*2^k - 1 is prime.at n=29A002236
• Numbers using only the digits 2 and 5, that are both curved and straight.at n=37A072961
• Structured disdyakis dodecahedral numbers (vertex structure 5).at n=14A100163
• Lexicographically earliest sequence of increasing numbers whose digits satisfy the "Fractal Jump" rule using only the digits 2 and 5: keep the first digit "d" of the sequence, then jump over the next "d" digits and keep the digit "e" on which you have landed. Jump now over the next "e" digits and keep the digit "f" on which you have landed, etc. The succession "def..." of kept digits is the sequence itself.at n=18A105647
• Numbers k such that k and k^2 use only the digits 0, 2, 5, 7 and 8.at n=19A136916
• Partial sums of A151791.at n=42A151792
• a(n) = sum(floor(sqrt(Bell(k))),k=0..n).at n=14A192571
• Number of partitions p of n such that (number of even numbers in p) >= (number of odd numbers in p).at n=41A241639
• Number of 3 X 3 symmetric matrices with row and column sums <= n.at n=8A244865
• G.f. (1-x)/(2*sqrt(5*x^2 + 2*x + 1)) - 1/2.at n=14A249908