A092643 Number of consecutive prime runs of 3 primes congruent to 3 mod 4 below 10^n.
0, 0, 1, 36, 323, 2480, 20947, 183898, 1621279, 14492365, 131016136
Offset: 1
Examples
a(5)=323 because 323 sets of 3 primes occur below 10^5, each run interrupted by a prime congruent to 1 mod 4.
Formula
Generate the prime sequence with primes labeled 1 mod 4 or 3 mod 4. Add count of primes to sequence if just 3 primes occur before interruption by a prime congruent to 1 mod 4.
Extensions
a(9)-a(11) from Chai Wah Wu, Mar 18 2018