20200820, 17:28  #958 
Nov 2016
2,347 Posts 
From the thread https://mersenneforum.org/showthread...=10354&page=10, searched up to n=6000, k=4 and k=5 (for the Riesel side) are still running ....

20200822, 20:38  #959 
Nov 2016
4453_{8} Posts 
All searched up to n=2^12
Riesel k=4, Sierp k=4, Sierp k=5, Sierp k=6 are still running 
20200824, 01:02  #960 
Nov 2016
2,347 Posts 
Exclusions for k<=12:
Riesel k=1: b=m^r with r>1 proven composite by full algebraic factors Riesel k=2: none Riesel k=3: none Riesel k=4: b==(4 mod 5): odd n, factor of 5; even n, algebraic factors b=m^2 proven composite by full algebraic factors Riesel k=5: b==(11 mod 12): covering set [2, 3] Riesel k=6: b==(34 mod 35): covering set [5, 7] b=6*m^2 with m==(2, 3 mod 5): even n, factor of 5; odd n, algebraic factors Riesel k=7: b==(11 mod 12): covering set [2, 3] Riesel k=8: b==(20 mod 21): covering set [3, 7] b==(83, 307 mod 455): covering set [5, 7, 13] b=m^3 proven composite by full algebraic factors Riesel k=9: b==(4 mod 5): odd n, factor of 5; even n, algebraic factors b==(9 mod 16): odd n, factor of 2; even n, algebraic factors b=m^2 proven composite by full algebraic factors Riesel k=10: b==(32 mod 33): covering set [3, 11] Riesel k=11: b==(14 mod 15): covering set [3, 5] b==(19 mod 20): covering set [2, 5] b=11*m^2 with m==(2, 3 mod 5): even n, factor of 5; odd n, algebraic factors Riesel k=12: b==(142 mod 143): covering set [11, 13] base 307: covering set [5, 11, 29] base 901: covering set [7, 11, 13, 19] Sierp k=1: b=m^r with odd r>1 proven composite by full algebraic factors Sierp k=2: none Sierp k=3: none Sierp k=4: b==(14 mod 15); covering set [3, 5] b=m^4 proven composite by full algebraic factors Sierp k=5: b==(11 mod 12): covering set [2, 3] Sierp k=6: b==(34 mod 35); covering set [5, 7] Sierp k=7: b==(5, 11, 23 mod 24): covering set [2, 3] Sierp k=8: b==(20 mod 21): covering set [3, 7] b==(47, 83 mod 195): covering set [3, 5, 13] base 467: covering set [3, 5, 7, 19, 37] base 722: covering set [3, 5, 13, 73, 109] b=m^3 proven composite by full algebraic factors base 128: no possible prime Sierp k=9: b==(19 mod 20): covering set [2, 5] Sierp k=10: b==(32 mod 33): covering set [3, 11] Sierp k=11: b==(14 mod 15): covering set [3, 5] b==(19 mod 20): covering set [2, 5] b==(5 mod 24): covering set [2, 3] Sierp k=12: b==(142 mod 143): covering set [11, 13] bases 296 and 901: covering set [7, 11, 13, 19] bases 562, 828, 900, and 1166: covering set [7, 13, 19] base 563 and 1433: covering set [5, 7, 13, 19, 29] base 597: covering set [5, 13, 29] Last fiddled with by sweety439 on 20200830 at 03:55 
20200829, 14:39  #961 
Nov 2016
2,347 Posts 
Update files.

20200829, 15:13  #962 
Nov 2016
2,347 Posts 
Primality certificates for the primes >= 300 digits for the proven or nearproven bases for the k such that gcd(k+1,b1) (+ for Sierpinski,  for Riesel) is not 1: (only for k < 1st CK)
S7: k=141 S13: k=11 (proven by N1method) S16: k=23 S25: k=61 S33: (k=319 and k=407 are only probable primes) k=11 k=31 (proven by N1method) k=63 k=251 k=305 S36: k=223 (proven by N+1method) (certificate for large prime factor for N+1) k=1000 k=1669 S37: k=19 S43: k=9 k=13 (proven by N1method) Last fiddled with by sweety439 on 20200829 at 15:13 
20200829, 16:48  #964 
Nov 2016
100100101011_{2} Posts 
Update files, all Sierp/Riesel k=1~7 (for bases 2<=b<=1024) are searched to n=6000

20200902, 16:06  #965  
Nov 2016
2,347 Posts 
Quote:
k=11 S72: k=141 S73: (k=14 is only probable prime) k=21 k=39 S75: k=11 S79: k=3 (proven by N+1method) (certificate for large prime factor for N+1) k=5 (proven by N1method) S80: k=552 S81: (k=311 is only probable prime) k=34 k=41 k=43 k=317 k=349 k=389 k=415 k=425 k=431 k=433 k=479 k=503 S88: k=8 S92: k=25 S93: (k=19 is only probable prime) k=3 (proven by N1method) k=31 k=43 S94: k=17 S97: k=26 k=68 k=87 k=122 S103: (k=13 is only probable prime) k=20 S105: (k=191 is only probable prime) k=39 k=183 S107: k=3 (proven by N+1method) S113: k=13 S115: k=50 

20200902, 20:11  #967 
Nov 2016
2,347 Posts 
https://docs.google.com/document/d/e...ZJlsvnJhll/pub
Update newest file for Riesel problems to include R126 
20200902, 21:32  #968 
Nov 2016
2,347 Posts 
Reserve R70

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