OFFSET
1,1
EXAMPLE
641 is in the sequence because 641 + 2 = 643, 641 + 2 + 4 = 647 is prime, the prime prior to 641 is 631, the prime after 647 is 653, and the corresponding differences are 10 or 6. The d-pattern is {10,2,4,6}.
CROSSREFS
KEYWORD
nonn
AUTHOR
Labos Elemer, Jan 26 2000
STATUS
approved