The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A340534 a(n) is the least product of n consecutive primes that is divisible by the sum of those primes, or 0 if there is no such product. 0

%I

%S 2,0,30,0,15015,0,37182145,9699690,33426748355,0,3710369067405,0,

%T 304250263527210,0,37420578814667938361329,0,

%U 18598027670889965365580513,0,107254825578022430263302818471,0,44510752614879308559270669665465,0,267064515689275851355624017992790,0,116431182179248680450031658440253681535,0

%N a(n) is the least product of n consecutive primes that is divisible by the sum of those primes, or 0 if there is no such product.

%C a(27) > 10^225 if it is not 0.

%C If n is even, a(n) is either A002110(n) or 0.

%C a(n) = A002110(n) for n in A051838.

%e a(5) = 15015 = 3*5*7*11*13 is the product of 5 consecutive primes and is divisible by 3+5+7+11+13 = 39.

%p f:= proc(n) local L,i,p;

%p L:= [seq(ithprime(i),i=1..n)]:

%p p:= convert(L,`*`);

%p if n::even then

%p if p mod convert(L,`+`) = 0 then return p else return 0 fi

%p else

%p do

%p p:= convert(L,`*`);

%p if p mod convert(L,`+`) = 0 then return p fi;

%p if p > 10^225 then return FAIL fi;

%p L:= [op(L[2..-1]),nextprime(L[-1])];

%p od

%p fi;

%p end proc:

%p map(f, [\$1..26]);

%Y Cf. A000210, A051838, A086487.

%K nonn

%O 1,1

%A _J. M. Bergot_ and _Robert Israel_, Jan 10 2021

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified July 23 17:41 EDT 2021. Contains 346259 sequences. (Running on oeis4.)