Status of search for primes k.2ⁿ+1

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

Recently reserved ranges | Reserve or submit a range

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

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

pc

pc

pc

pc

X

33

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

35

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

37

X

X

X

X

X

X

X

X

X

X

sh

sh

sh

sh

sh

39

X

X

X

X

X

X

X

sh

sh

sh

41

X

X

ho

43

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

45

X

X

X

X

X

X

X

X

X

X

sh

sh

sh

sh

sh

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

X

X

X

X

X

X

X

X

X

X

51

X

X

X

X

X

X

X

X

X

X

sh

sh

sh

sh

sh

53

X

X

X

X

X

X

X

X

X

X

55

X

X

X

X

X

X

X

X

X

X

57

X

X

X

X

X

sh

sh

sh

sh

sh

59

X

X

X

X

X

X

X

X

X

X

61

X

X

X

X

X

X

X

X

X

X

63

X

X

X

X

X

sh

sh

sh

sh

sh

65

X

X

X

X

X

sh

sh

sh

sh

sh

67

X

X

X

X

X

sh

sh

sh

sh

sh

69

X

X

X

X

X

X

X

X

X

X

71

X

X

X

X

X

73

X

X

X

X

X

75

X

X

X

X

X

77

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

79

X

X

X

X

X

X

81

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

83

X

X

X

X

X

X

X

X

X

X

85

X

X

X

X

X

87

X

X

X

X

X

89

X

X

X

X

X

91

X

X

X

X

X

93

X

X

X

X

X

95

X

X

X

X

X

97

X

X

X

X

X

99

X

X

X

X

X

sh

sh

sh

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	X	X	X	X	X	X	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