120228

Appears in sequences

• Numbers n with the property that it is possible to write the base 2 expansion of n as concat(a_2,b_2), with a_2>0 and b_2>0 such that, converting a_2 and b_2 to base 10 as a and b, we have (sigma(a)-a)*(sigma(b)-b) = sigma(n).at n=4A259832
• Number of compositions of n that are not a twin (x,x) but have adjacent equal parts.at n=18A348382