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A092663
Number of consecutive prime runs of 10 primes congruent to 1 mod 4 below 10^n.
3
0, 0, 0, 0, 0, 5, 19, 323, 3653, 37544, 381413, 3799344, 37591054
OFFSET
1,6
FORMULA
Generate the prime sequence with primes labeled 1 mod 4 or 3 mod 4. Add count of primes to sequence if just 10 primes occur before interruption by a prime congruent to 3 mod 4
EXAMPLE
a(6)=5 because 5 sets of 10 primes occur below 10^6, each run interrupted by a prime congruent to 3 mod 4. These runs start at prime(31798)=373649, prime(41181)=495377, at prime(42241)=509389, at prime(50017)=612109, *not* at prime(61457) which has a larger run length, and at prime(63146)=789097.
CROSSREFS
KEYWORD
more,nonn,hard
AUTHOR
Enoch Haga, Mar 02 2004
EXTENSIONS
a(9) and a(10) from Sean A. Irvine, Oct 06 2011
a(11) from Chai Wah Wu, Mar 18 2018
a(12) and a(13) from Lucas A. Brown, Oct 15 2024
STATUS
approved