A233420 Minimal number of c-squares (A020330) and/or 1's which add to n.
1, 2, 1, 2, 3, 2, 3, 4, 3, 1, 2, 3, 2, 3, 1, 2, 3, 2, 3, 2, 3, 4, 3, 4, 2, 3, 4, 3, 4, 2, 3, 4, 3, 4, 3, 1, 2, 3, 2, 3, 4, 3, 4, 5, 1, 2, 3, 2, 3, 4, 2, 3, 4, 1, 2, 3, 2, 3, 4, 2, 3, 4, 1, 2, 3, 2, 3, 4, 2, 3, 4, 2, 2, 3, 3, 3, 4, 2, 3, 4, 2, 3, 3, 3
Offset: 1
Keywords
Examples
For n=33, we have 33=15+15+3. Since 33 is not in union of {1} and c-squares and is not a sum of two such numbers, then a(33)=3.
Programs
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PARI
v=vector(10^5,n,n+n<<#binary(n)); \\ choose large enough that v[#v] > n for a(n) below. a(n)=if(setsearch(v,n),return(1));if(n<3,return(n));my(where=setsearch(v,n+1,1),t=n);if(!where,where=setsearch(v,n,1));forstep(i=where-1,1,-1,t=min(w(n-v[i]),t); if(t==1,return(2))); t+1 \\ Charles R Greathouse IV, Dec 10 2013
Comments