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%I #8 May 05 2018 08:22:47
%S 1,2,4,7,16,19,52,55,160,163,484,487,1456,1459,4372,4375,13120,13123,
%T 39364,39367,118096,118099,354292,354295
%N First differences of A302774; Number of terms in A303762 that have prime(n) as their largest prime factor (A006530).
%C For n >= 1, the difference A000079(n-1) - a(n): 0, 0, 0, 1, 0, 13, 12, 73, 96, 349, 540, 1561, 2640, 6733, 12012, 28393, 52416, 117949, 222780, 484921, 930480, 1979053, 3840012, ..., indicates how many squarefree numbers A303762 misses in each round. The first of these is 70 missed at the round 4.
%C The first differences of these terms is: 1, 2, 3, 9, 3, 33, 3, 105, 3, 321, 3, 969, 3, 2913, 3, 8745, 3, 26241, 3, 78729, 3, 236193, 3, ... which after the first two initial terms seem to be an interleaving of sequences A010701 and A036543.
%F a(n) = A302774(n+1) - A302774(n).
%Y Cf. A010701, A036543, A302774, A303762.
%K nonn
%O 1,2
%A _Antti Karttunen_, May 05 2018