A046425 Numbers requiring 5 steps to reach a prime under the prime factor concatenation procedure.

14, 34, 147, 164, 183, 214, 216, 230, 236, 248, 252, 276, 285, 309, 324, 335, 404, 405, 444, 482, 484, 486, 508, 520, 527, 540, 550, 570, 580, 633, 636, 638, 658, 689, 704, 730, 738, 802, 814, 852, 915, 935, 954, 959, 960, 981, 996, 1004, 1037, 1046, 1058

Offset

0,1

Links

Table of n, a(n) for n=0..50.

Patrick De Geest, Home Primes

Example

14 = 2*7 -> 27 = 3*3*3 -> 333 = 3*3*37 -> 3337 = 47*71 -> 4771 = 13*367 and 13367 is prime.

Crossrefs

Cf. A037271, A046411.

Sequence in context: A120875 A103533 A269663 * A018950 A159242 A054309

Adjacent sequences: A046422 A046423 A046424 * A046426 A046427 A046428

Keyword

nonn,base

Author

Patrick De Geest, Jun 15 1998

Status

approved