213193

Properties

Appears in sequences

• a(1) = 3; a(2n) = smallest prime starting (in the most significant digits) with a(2n-1) (i.e., as a right concatenation of a(2n-1) and a number with no insignificant zeros); a(2n+1) = smallest prime ending in (the least significant digits) a(2n-1). Alternate left and right concatenation yielding primes.at n=5A069615
• a(1) = 3; a(2n) = smallest prime starting (most significant digits) with a(2n-1). a(2n+1) = smallest prime ending (least significant digits)in a(2n).at n=5A069630
• 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, -1), (-1, -1, 0), (-1, 0, 0), (1, 0, 1), (1, 1, -1)}.at n=11A148825
• Number of "Euclidean primes" with respect to the first n primes.at n=21A283936
• Prime numbersat n=19062