OFFSET
1,4
COMMENTS
Similar to A036440, but not requiring 1 to be first and n to be last.
FORMULA
For n>1, a(n) = A103839(n)/2.
EXAMPLE
a(5)=2 since 1,4,3,2,5 and 3,4,1,2,5 have the property that the sum of each adjacent pair is prime.
CROSSREFS
KEYWORD
nonn,nice
AUTHOR
EXTENSIONS
More terms from Max Alekseyev, Jan 04 2008
a(25)-a(28) from Giovanni Resta, Apr 01 2014
STATUS
approved