A253897 Numbers n such that the sequence A127644 with a(1) = n is conjectured to give a permutation of the natural numbers.
3, 4, 5, 6, 8, 9, 10, 12, 14, 15, 16, 18, 20, 21, 22, 24, 28, 30, 33, 35, 36, 39, 40, 44, 45, 48, 50, 55, 56, 60, 63, 66, 70, 72, 75, 77, 78, 80, 84, 88, 90, 91, 99, 102, 104, 105, 108, 112, 117, 120, 126, 130, 132, 135, 140, 144, 150, 154, 160, 165, 168, 176, 180, 182, 195, 198, 208
Offset: 1
Keywords
Examples
a(1) = 3 because A127644 is conjectured to be a permutation of the natural numbers.
Programs
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PARI
b(r)=v=[r];n=1;while(n<100,p=prod(i=1,#v,v[i]);if(p*n\(vecsum(v)+n)==p*n/(vecsum(v)+n)&&!vecsearch(vecsort(v),n),v=concat(v,n);n=0);n++);#v r=1;while(r<500,if(b(r)>50,print1(r,", "));r++)
Comments