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 A145992 Run lengths of 2 or more consecutive primes of the form 4k+3. 5
 2, 2, 2, 2, 2, 2, 2, 2, 4, 2, 2, 2, 2, 7, 2, 2, 2, 2, 3, 2, 2, 5, 2, 2, 2, 2, 2, 3, 2, 3, 2, 2, 5, 5, 2, 2, 4, 2, 2, 3, 2, 2, 3, 4, 2, 2, 3, 3, 2, 3, 2, 3, 2, 2, 2, 2, 2, 3, 3, 2, 3, 3, 2, 4, 2, 2, 3, 2, 2, 3, 2, 2, 2, 2, 4, 2, 2, 3, 2, 3, 3, 2, 3, 4, 2, 2, 2, 4, 2, 2, 3, 2, 2, 2, 2, 2, 3, 2, 3, 2, 3, 3 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 REFERENCES Enoch Haga, Exploring Primes on Your PC and the Internet, 1994-2007. Pp. 30-31. ISBN 978-1-885794-24-6 LINKS Harvey P. Dale, Table of n, a(n) for n = 1..1000 EXAMPLE a(1) = 2 counts the two 3's from A039702(4) to A039072(5). a(9) = 4 counts the four 3's from A039702(46) to A039072(49). a(14)= 7 counts the seven 4's from A039702(90) to A039072(96). MAPLE A145992 := proc() local m, p, r, i ; m := 3 ; p := 2 ; r := 0 ; for i from 2 to 1000 do if modp(p, 4) = m then r := r+1 ; else if r > 1 then printf("%d, ", r) ; end if; r := 0; end if; p := nextprime(p) ; end do: end proc: A145992() ; # R. J. Mathar, Aug 29 2018 MATHEMATICA Most[Length /@ Select[ SplitBy[ Prime@ Range@ 780, Mod[#, 4] &], Mod[#[[1]], 4] == 3 && Length[#] > 1 &]] (* Giovanni Resta, Aug 29 2018 *) Length/@Select[Split[Table[If[Mod[n, 4]==3, 1, 0], {n, Prime[Range[ 1000]]}]], FreeQ[ #, 0]&]/.(1->Nothing) (* Harvey P. Dale, Jul 27 2020 *) CROSSREFS Cf. A039702, A055623, A145986, A145988, A145989, A145990, A145991, A145993, A145994. Sequence in context: A277090 A103376 A189819 * A045818 A064128 A248774 Adjacent sequences: A145989 A145990 A145991 * A145993 A145994 A145995 KEYWORD easy,nonn AUTHOR Enoch Haga, Oct 26 2008 EXTENSIONS Corrected by R. J. Mathar, Aug 29 2018 STATUS approved

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Last modified February 28 01:06 EST 2024. Contains 370379 sequences. (Running on oeis4.)