This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A257755 #10 Aug 28 2015 18:54:10 %S A257755 34933,295927,312157,346777,379231,417091,444853,471773,576077,582133, %T A257755 1384753,1462579,1687397,1689991,1713337,1861289,1944869,3211183, %U A257755 3654223,4092493,4358737,5134531,5410051,5564557,6863671,7061321,7343659,7531889,7622221,7817591 %N A257755 Quasi-Carmichael numbers to exactly five bases. %e A257755 a(1) = 34933 because this is the first squarefree composite number n such that exactly five integers except 0 exist such that for every prime factor p of n applies that p+b divides n+b (-178, -175, -173, -157, -133): 34933=181*193 and 3, 15 both divide 34755 and 6, 18 both divide 34758 and 18, 20 both divide 34760 and 24, 36 both divide 34776 and 48, 60 both divide 34800. %o A257755 (PARI) for(n=2, 1000000, if(!isprime(n), if(issquarefree(n), f=factor(n); k=0; for(b=-(f[1, 1]-1), n, c=0; for(i=1, #f[, 1], if((n+b)%(f[i, 1]+b)>0, c++)); if(c==0, if(!b==0, k++))); if(k==5, print1(n, ", "))))) %Y A257755 Cf. A257750 (every number of bases). %Y A257755 Cf. A257751, A257752, A257753, A257754, A257756, A257757, A258842 (1, 2, 3, 4, 6, 7 and 8 bases). %Y A257755 Cf. A257758 (first occurrences). %K A257755 nonn %O A257755 1,1 %A A257755 _Tim Johannes Ohrtmann_, May 12 2015