OFFSET
1,2
COMMENTS
In the prime circle problem we seek to arrange the numbers 1 to 2n around a circle so that the sum of each pair of adjacent numbers is prime. To display the solution, we unroll the circle starting at 1.
REFERENCES
R. K. Guy, Unsolved Problems Number Theory, Section C1.
LINKS
T. D. Noe, Rows n=1..50 of triangle, flattened
Eric Weisstein's World of Mathematics, Prime Circle
EXAMPLE
Triangle begins:
1, 2;
1, 2, 3, 4;
1, 4, 3, 2, 5, 6;
1, 2, 3, 8, 5, 6, 7, 4;
...
CROSSREFS
KEYWORD
AUTHOR
T. D. Noe, Oct 16 2007
STATUS
approved