Status of search for primes k.2ⁿ+1

31 < k < 99 & 500,000 < n < 1,500,000

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Color legend:

completed (X)

being tested

available

k \ n x 1000

1000-1020

1020-1040

1040-1060

1060-1080

1080-1100

1100-1120

1120-1140

1140-1160

1160-1180

1180-1200

1200-1220

1220-1240

1240-1260

1260-1280

1280-1300

1300-1320

1320-1340

1340-1360

1360-1380

1380-1400

1400-1420

1420-1440

1440-1460

1460-1480

1480-1500

31

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37

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sh

sh

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39

X

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sh

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41

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cs

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43

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45

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sh

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47

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49

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51

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53

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55

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57

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59

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61

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63

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65

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67

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69

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71

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73

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75

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77

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79

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81

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83

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85

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87

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89

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91

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93

sh

sh

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95

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97

X

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99

sh

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sh

sh

k \ n x 1000	1500-1520	1520-1540	1540-1560	1560-1580	1580-1600	1600-1620	1620-1640	1640-1660	1660-1680	1680-1700	1700-1720	1720-1740	1740-1760	1760-1780	1780-1800	1800-1820	1820-1840	1840-1860	1860-1880	1880-1900	1900-1920	1920-1940	1940-1960	1960-1980	1980-2000
31	X	X	X	X	X	ho	ho	ho
33	X	X	X	X	X	X	X	X	X	X
35	X	X	X	X	X	X	X	X	X	X	X	X	X (to 1750)
37
39
41
43	X	X	X	X	X	X	X	X	X	X	X	X	X (to 1750)
45
47	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
49
51
53
55
57
59
61
63
65
67
69
71
73
75
77
79
81	X	X	X	X	X
83
85
87
89
91
93
95
97
99