A259283 Quasi-Carmichael numbers to at least one positive base.

165, 231, 273, 357, 399, 598, 715, 935, 1015, 1105, 1547, 1595, 1885, 1886, 2015, 2093, 2387, 2397, 2451, 2465, 2585, 2679, 2737, 2821, 2915, 3059, 3445, 3913, 3965, 4123, 4991, 5015, 5467, 5719, 6097, 6545, 7055, 7189, 7285, 7553, 7843, 8555, 8569, 8715, 8855

Offset: 1

Author

Tim Johannes Ohrtmann, Jun 23 2015

Keywords

• nonn

Examples

			a(1) = 165 because this is the first squarefree composite number n such that at least one positive integer b except 0 exists such that for every prime factor p of n applies that p+b divides n+b (3): 165=3*5*11 and 6, 8, 14 all divide 168.
		

Links

• Tim Johannes Ohrtmann, Table of n, a(n) for n = 1..2963

Crossrefs

Cf. A257750, A257759, A259282.

Programs

PARI

for(n=2, 1000000, if(!isprime(n), if(issquarefree(n), f=factor(n); b=0; until(c==0 || b==n, b++; c=0; for(i=1, #f[, 1], if((n+b)%(f[i, 1]+b)>0, c++)); if(c==0, print1(n, ", "))))))