1,2
Take the absolute value of the difference between counts of runs of 2 primes congruent to 1 mod 4 and 3 mod 4.
a(2)=3 because in A092639 the count is 2 and in A092640 the count is 5. 5-3=2.
Cf. A092639 A092640.
Sequence in context: A034464 A116696 A000220 * A077449 A152232 A183038
Adjacent sequences: A092638 A092639 A092640 * A092642 A092643 A092644
more,nonn
Enoch Haga (Enokh(AT)comcast.net), Mar 02 2004