OFFSET
1,2
LINKS
Carole Dubois, Table of n, a(n) for n = 1..4999
Carole Dubois, Hexagonal spiral for A363938.
Carole Dubois, Scatterplot of A363938(n)
Carole Dubois, Hexagons with spiral
EXAMPLE
a(11) = 8 because the neighbors of the 11th hexagon are 3, 13, 17, 21, 33, 37, which do not have any common prime divisor with 8.
CROSSREFS
KEYWORD
nonn
AUTHOR
Carole Dubois, Jun 29 2023
STATUS
approved