A378139 Smallest prime number such that the number of distinct prime factors with multiplicity of its 9's complement is equal to n. If no such number exists, return -1.

2, 3, 23, 11, 19, 263, 167, 103, 487, 1039, 7951, 5903, 28319, 107071, 67231, 590399, 180799, 344639, 1480319, 12181759, 4757119, 10871039, 1611391, 140167679, 203082239, 228248063, 530237951, 1812718591, 5302379519, 13295347711, 12758476799, 132953477119, 1410065407

Offset

1,1

Links

Michael S. Branicky, Table of n, a(n) for n = 1..1000 (terms 1..37 from Jean-Marc Rebert)

Example

2 is prime, 9-2 = 7 and bigomega(7) = 1.

Prog

(PARI) nc(n) = my(e=length(Str(n))); 10^e-1 - n; \\ A061601
a(n) = my(p=2); while (bigomega(nc(p)) != n, p = nextprime(p+1)); p; \\ Michel Marcus, Jan 08 2025

Crossrefs

Cf. A000040, A001221, A001222, A061601. A377471,

Sequence in context: A282795 A071819 A329916 * A085946 A280894 A042585

Adjacent sequences: A378136 A378137 A378138 * A378140 A378141 A378142

Keyword

nonn,base

Author

Jean-Marc Rebert, Jan 08 2025

Status

approved