A215110 Smallest integer k such that prime(n+1) = floor(x*prime(n)) where x = (k/(k-1))^n.

3, 4, 7, 8, 22, 19, 44, 35, 35, 103, 55, 96, 185, 128, 109, 130, 344, 167, 265, 484, 230, 359, 285, 250, 498, 889, 571, 1014, 648, 242, 804, 616, 1524, 447, 1757, 795, 849, 1259, 951, 1009, 2468, 713, 2760, 1721, 2978, 728, 787, 2166, 3733, 2316, 1724, 4170

Offset

1,1

Links

Michel Lagneau, Table of n, a(n) for n = 1..350

Example

a(3) = 7 because prime(4) = floor(prime(3) * (7/6)^3) = floor(5*1.587962…) = 7.

Maple

with(numtheory):for n from 1 to 85 do:i:=0:p0:=ithprime(n):p1:=ithprime(n+1):for k from 2 to 10^8 while(i=0) do:x:=(k/(k-1))^n:if p1=floor(p0*x) then i:=1 : printf(`%d, `, k):else fi:od:od:

Crossrefs

Cf. A000040.

Sequence in context: A130420 A214096 A169943 * A101715 A249751 A169893

Adjacent sequences: A215107 A215108 A215109 * A215111 A215112 A215113

Keyword

nonn

Author

Michel Lagneau, Aug 03 2012

Status

approved