A271443 Earliest start of a run of n numbers divisible by a cube larger than one.

8, 80, 1375, 22624, 18035622, 4379776620, 1204244328624, 2604639091138248, 2604639091138248

Offset

1,1

Comments

a(5)-a(7) were found by Donovan Johnson.

Links

Table of n, a(n) for n=1..9.

Jean-Marie De Koninck, Those Fascinating Numbers, Amer. Math. Soc., (2009), page 63.

Example

a(9) = 2604639091138248 and the following 8 numbers are divisible by 2^3, 11^3, 5^3, 17^3, 7^3, 13^3, 3^3, 19^3, and 2^4, respectively.

Mathematica

a[n_] := Block[{k=1, c=0}, While[ c<n, If[ Max[ Last /@ FactorInteger[ ++k]] < 3, c=0, c++]];  k-n+1]; Array[a, 4]

Crossrefs

Cf. A046099, A068140, A122692, A271444, A271445, A271446, A271447.

Cf. A045882, A330480, A330481, A330482, A330486, A330483, A330484, A330485.

Sequence in context: A222825 A057707 A222671 * A347768 A240325 A145606

Adjacent sequences: A271440 A271441 A271442 * A271444 A271445 A271446

Keyword

nonn,more

Author

Giovanni Resta, Apr 23 2016

Status

approved