1,2

P. De Geest, Repunits prime factors

Eric Weisstein's World of Mathematics, Repunit

a(n)=10 -> 11*41*271*9091 ->1(1)*4(1)*27(1)*909(1).

Cf. A000042, A004022, A046053.

Sequence in context: A018401 A049332 A096570 this_sequence A133040 A018424 A000675

Adjacent sequences: A046427 A046428 A046429 this_sequence A046431 A046432 A046433

nonn,more,base

Patrick De Geest (pdg(AT)worldofnumbers.com), Jul 15 1998.