22522
domain: N
Appears in sequences
- Numbers k such that the continued fraction for sqrt(k) has period 69.at n=20A020408
- Numbers having four 2's in base 10.at n=26A043500
- Length of hypotenuse squared in right triangle formed by a palindromic spiral plotted in Cartesian coordinates.at n=19A048871
- Number of optimal binary prefix-free codes with n words all ending in 1.at n=44A055167
- Positions where number of periodic partitions increases.at n=43A059994
- Numbers using only the digits 2 and 5, that are both curved and straight.at n=34A072961
- Number of anti-divisors of n (A066272) sets a record.at n=25A073638
- Palindromic even squarefree numbers with an even number of distinct prime factors.at n=19A075811
- Palindromic even numbers with exactly 2 prime factors (counted with multiplicity). Equivalently, palindromic numbers of the form 2*p with p prime.at n=14A075813
- n-th largest palindrome whose digit sum is n.at n=12A082265
- Palindromes made of only prime digits.at n=42A084983
- Lesser of a pair of records in A066272.at n=1A093071
- Palindromic numbers with property that sum of digits is prime and number of prime digits is prime.at n=34A093807
- Palindromic Smith numbers.at n=16A098834
- Decimal Goedelization of antitheorems from propositional calculus, in Richard C. Schroeppel's metatheory of A101273.at n=17A100200
- 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=16A105647
- Near-repdigit semiprimes with 2 as repeated digit.at n=19A105983
- Palindromic primes in base 7 (written in base 7).at n=21A117702
- Number of (n+2) X (3+2) 0..1 arrays with each 3 X 3 subblock having clockwise perimeter pattern 00010101 01010101 or 01010111.at n=5A260133
- Number of (n+2)X(6+2) 0..1 arrays with each 3X3 subblock having clockwise perimeter pattern 00010101 01010101 or 01010111.at n=2A260136