A157942 Numbers n divisible by the largest prime <= sqrt(n), A007917(A000196(n)).

4, 6, 8, 9, 12, 15, 18, 21, 24, 25, 30, 35, 40, 45, 49, 56, 63, 70, 77, 84, 91, 98, 105, 112, 119, 121, 132, 143, 154, 165, 169, 182, 195, 208, 221, 234, 247, 260, 273, 286, 289, 306, 323, 340, 357, 361, 380, 399, 418, 437, 456, 475, 494, 513, 529, 552, 575, 598

Offset

1,1

Comments

Includes squares of primes (A001248; exactly the cases where we have "=" in the definition) and products of pairs of consecutive primes (A006094) as subsequences.

Links

Table of n, a(n) for n=1..58.

Mathematica

Select[Range[4, 599], IntegerQ[#/Prime[PrimePi[Sqrt[#]]]]&] (* Jayanta Basu, May 03 2013 *)

Prog

(PARI) for( n=4, 999, n % precprime(sqrtint(n)) | print1(n", "))

Crossrefs

Sequence in context: A130074 A304242 A067012 * A122786 A092630 A079142

Adjacent sequences: A157939 A157940 A157941 * A157943 A157944 A157945

Keyword

nonn

Author

M. F. Hasler, Mar 09 2009

Status

approved