A303749 First differences of A302774; Number of terms in A303762 that have prime(n) as their largest prime factor (A006530).

1, 2, 4, 7, 16, 19, 52, 55, 160, 163, 484, 487, 1456, 1459, 4372, 4375, 13120, 13123, 39364, 39367, 118096, 118099, 354292, 354295

Offset

1,2

Comments

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.

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.

Links

Table of n, a(n) for n=1..24.

Formula

a(n) = A302774(n+1) - A302774(n).

Crossrefs

Cf. A010701, A036543, A302774, A303762.

Sequence in context: A280031 A135131 A032363 * A239390 A338647 A372097

Adjacent sequences: A303746 A303747 A303748 * A303750 A303751 A303752

Keyword

nonn

Author

Antti Karttunen, May 05 2018

Status

approved