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 A145991 Final prime in a run of more than 1 consecutive primes == 1 (mod 4). 5
 17, 41, 101, 113, 197, 233, 281, 317, 353, 409, 461, 521, 617, 677, 709, 773, 809, 857, 881, 941, 1013, 1097, 1117, 1217, 1249, 1301, 1381, 1433, 1493, 1553, 1601, 1613, 1657, 1697, 1721, 1741, 1801, 1877, 1901, 1949, 1997, 2081, 2129, 2141, 2161, 2237 (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 EXAMPLE a(1)=17 because this sequence includes consecutive runs of any length and this ending term > 1 in a run of 2 (comprising 13 and 17) is 17. PROG (UBASIC) 10 'cluster primes 20 C=1 30 input "end #"; L 40 for N=3 to L step 2 50 S=int(sqrt(N)) 60 for A=3 to S step 2 70 B=N/A 80 if int(B)*A=N then cancel for:goto 170 90 next A 100 C=C+1 110 E=N/4:E=int(E):R=N-(4*E) 120 if R=1 then print N; :C1=C1+1:T1=T1+1:print T1 130 if R=3 then T1=0 140 if R=3 then print " "; N; :C3=C3+1:T2=T2+1:print T2 150 if R=1 then T2=0 160 if T1>10 or T2>10 then stop 170 next 180 print "Total primes="; C; :print "Type A"; C1; "Type B"; C3 CROSSREFS Cf. A055623, A054624, A145986, A145988- A145994 Sequence in context: A070179 A155072 A243451 * A089637 A139961 A188661 Adjacent sequences:  A145988 A145989 A145990 * A145992 A145993 A145994 KEYWORD easy,nonn AUTHOR Enoch Haga, Oct 26 2008 STATUS approved

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Last modified May 23 13:32 EDT 2019. Contains 323514 sequences. (Running on oeis4.)