1,3

Take the absolute value of differences between counts of runs of single nonprimes congruent to 1 mod 4 and 3 mod 4

a(3)=2 because in A093183 the count is 74 and in A093184 the count is 76. 76-74=2.

Cf. A093183 A093184 A092636 A092637 A092638.

Sequence in context: A121624 A103019 A101823 this_sequence A082459 A129831 A101713

Adjacent sequences: A093394 A093395 A093396 this_sequence A093398 A093399 A093400

nonn

Enoch Haga (Enokh(AT)comcast.net), Mar 30 2004