A162422 Numbers with at least 2 different numbers of digits among their prime factors.
22, 26, 33, 34, 38, 39, 44, 46, 51, 52, 55, 57, 58, 62, 65, 66, 68, 69, 74, 76, 77, 78, 82, 85, 86, 87, 88, 91, 92, 93, 94, 95, 99, 102, 104, 106, 110, 111, 114, 115, 116, 117, 118, 119, 122, 123, 124, 129, 130, 132, 133, 134, 136, 138, 141, 142, 145, 146, 148, 152
Offset: 1
Examples
1111 = 11*101 has factors with different digital lengths. Also it is the first occurrence that differs from A084891.
Programs
-
PARI
factorrough(m,n) = { local(x,a,j,f,ln); for(x=m,n, f=0; a = ifactor(x); for(j=2,length(a), ln=length(Str(a[j-1])); if(length(Str(a[j]))!=ln,f=1;break);); if(f,print1(x","));); }
Extensions
Offset set to 1, definition shortened - R. J. Mathar, Sep 16 2009
Comments