A092641
Absolute value of difference between counts of uninterrupted runs of 2 primes in A092639 and A092640.
Original entry on oeis.org
0, 3, 6, 15, 29, 117, 500, 1136, 4475, 3065, 8440
Offset: 1
a(2)=3 because in A092639 the count is 2 and in A092640 the count is 5. 5 - 3 = 2.
A093185
Number of consecutive runs of 2 odd nonprimes congruent to 1 mod 4 below 10^n.
Original entry on oeis.org
1, 4, 33, 309, 2805, 25566, 230989, 2106529, 19303539, 177948527, 1649241049, 15360074924, 143682925080
Offset: 1
a(3)=33 because 33 nonprime runs of 2 occur below 10^3, each run interrupted by a nonprime congruent to 3 mod 4
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A091113 = Select[4 Range[0, 10^4] + 1, ! PrimeQ[#] &];
A091236 = Join[{0}, Select[4 Range[0, 10^4] + 3, ! PrimeQ[#] &]];
lst = {}; Do[If[Length[s = Select[A091113, Between[{A091236[[i]], A091236[[i + 1]]}]]] == 2, AppendTo[lst, Last[s]]], {i, Length[A091236] - 1}]; Table[Count[lst, x_ /; x < 10^n], {n, 4}] (* Robert Price, May 30 2019 *)
A093398
Absolute value of difference between counts of uninterrupted runs of 2 nonprimes in A093185 and A093186.
Original entry on oeis.org
1, 0, 3, 2, 43, 85, 42, 36, 3823, 192, 5114, 2797, 148220
Offset: 1
a(3)=3 because in A093185 the count is 33 and in A093186 the count is 36. 36-33=3.
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