|
%I #5 Jul 10 2020 13:04:02
%S 1,0,1,-1,0,2,-1,-1,0,3,-3,0,0,1,1,-2,0,4,-4,0,0,0,1,-1,0,0,5,-5,0,0,
%T 0,3,-3,0,0,0,0,0,0,0,1,1,-2,6,-6,0,0,0,0,0,0,0,1,-1,0,0,0,0,0,0,0,0,
%U 0,0,0,0,0,4,-4,7,-7,0,0,0,0,0,0,1,-1,0,0,0,0,0,0,2,-2,0,0,0,1,-1,0,0
%N First differences of exponents of consecutive prime powers.
%C a(n) = A025474(n+1) - A025474(n).
%t Join[{1},Differences[FactorInteger[#][[1,2]]&/@Select[Range[ 400], PrimePowerQ]]] (* _Harvey P. Dale_, Jul 10 2020 *)
%Y Cf. A088233, A000961, A057820.
%K sign
%O 1,6
%A _Reinhard Zumkeller_, Sep 25 2003
|
