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Counts where both the odd composites (starting from 1) 1 mod 4 and 3 mod 4 are equal.
2

%I #6 Sep 08 2023 21:04:55

%S 5238,5241,5242,5243,5244,5245,5246,5247,5248,5249,5250,5255,129008,

%T 129009,129010,129012,129020,129021,129022,129023,129024,129025,

%U 129026,129027,129028,129029,129030,129031,129032,129033,129058,129059,129060

%N Counts where both the odd composites (starting from 1) 1 mod 4 and 3 mod 4 are equal.

%F Run separate counts of odd composites 1 mod 4 and 3 mod 4. When the count is equal, record the count.

%e At 26829 1 mod 4 and 26835 3 mod 4, the count of odd composites is equal for each run at 5238; so a(1)=5238. [Compare to the prime 26833 1 mod 4 where equality occurs at count 1471 and the first reversal in the race occurs at 26861.]

%Y Cf. A093180, A093181, A007350, A007351, A038691.

%K easy,nonn

%O 1,1

%A _Enoch Haga_, Mar 27 2004