28181

Properties

Appears in sequences

• Numbers k such that the continued fraction for sqrt(k) has odd period and if the last term of the periodic part is deleted the two central terms are both 13.at n=24A031601
• Number of ternary rooted trees with n nodes and height at most 6.at n=16A036374
• Primes whose consecutive digits differ by 6 or 7.at n=20A048418
• Revert transform of 2*x*(1 - x + x^4 - x^5)-x/(1+x).at n=9A049179
• Sum of composite numbers between prime p and nextprime(p) is palindromic.at n=29A054266
• Primes p such that their cubes are pandigital.at n=31A124629
• Integer part of Gauss's Arithmetic-Geometric Mean M(2,n^4).at n=21A127765
• 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), (-1, 0, 1), (1, 0, -1), (1, 0, 0), (1, 1, 0)}.at n=8A150365
• Lesser of consecutive primes whose average is a palindromic number.at n=39A242387
• Primes formed by an m-digit prime concatenated with its last (m-1) digits, for m > 1.at n=14A252667
• Primes of form n^2 + 625.at n=31A256777
• Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 470", based on the 5-celled von Neumann neighborhood.at n=41A272421
• Primes whose index is divisible by the product of its digits.at n=32A306766
• Least number with exactly n distinct divisors of prime indices. Position of first appearance of n in A370820.at n=22A371131
• Sorted list of positions of first appearances in the sequence A370820, which counts distinct divisors of prime indices.at n=31A371181
• Primes having only {1, 2, 8} as digits.at n=31A385775
• Prime numbersat n=3072