Curzon numbers: Difference between revisions

</pre>

=={{header|Python}}==

<lang python>def is_Curzon(n, k):

return (k**n + 1) % (k * n + 1) == 0

for k in [2, 4, 6, 8, 10]:

n, curzons = 1, []

while len(curzons) < 1000:

if is_Curzon(n, k):

curzons.append(n)

n += 1

print(f'Curzon numbers with k = {k}:')

for i, c in enumerate(curzons[:50]):

print(f'{c: 5,}', end='\n' if (i + 1) % 25 == 0 else '')

print(f' Thousandth Curzon with k = {k}: {curzons[999]}.\n')

</lang>{{out}}

<pre>

Curzon numbers with k = 2:

1 2 5 6 9 14 18 21 26 29 30 33 41 50 53 54 65 69 74 78 81 86 89 90 98

105 113 114 125 134 138 141 146 153 158 165 173 174 186 189 194 198 209 210 221 230 233 245 249 254

Thousandth Curzon with k = 2: 8646.

Curzon numbers with k = 4:

1 3 7 9 13 15 25 27 37 39 43 45 49 57 67 69 73 79 87 93 97 99 105 115 127

135 139 153 163 165 169 175 177 183 189 193 199 205 207 213 219 235 249 253 255 265 267 273 277 279

Thousandth Curzon with k = 4: 9375.

Curzon numbers with k = 6:

1 6 30 58 70 73 90 101 105 121 125 146 153 166 170 181 182 185 210 233 241 242 266 282 290

322 373 381 385 390 397 441 445 446 450 453 530 557 562 585 593 601 602 605 606 621 646 653 670 685

Thousandth Curzon with k = 6: 20717.

Curzon numbers with k = 8:

1 14 35 44 72 74 77 129 131 137 144 149 150 185 200 219 236 266 284 285 299 309 336 357 381

386 390 392 402 414 420 441 455 459 470 479 500 519 527 536 557 582 600 602 617 639 654 674 696 735

Thousandth Curzon with k = 8: 22176.

Curzon numbers with k = 10:

1 9 10 25 106 145 190 193 238 253 306 318 349 385 402 462 486 526 610 649 658 678 733 762 810

990 994 1,033 1,077 1,125 1,126 1,141 1,149 1,230 1,405 1,422 1,441 1,485 1,509 1,510 1,513 1,606 1,614 1,630 1,665 1,681 1,690 1,702 1,785 1,837

Thousandth Curzon with k = 10: 46845.