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.
2, 0, 30, 0, 15015, 0, 37182145, 9699690, 33426748355, 0, 3710369067405, 0, 304250263527210, 0, 37420578814667938361329, 0, 18598027670889965365580513, 0, 107254825578022430263302818471, 0, 44510752614879308559270669665465, 0, 267064515689275851355624017992790, 0, 116431182179248680450031658440253681535, 0
Offset: 1
Keywords
Examples
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.
Programs
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Maple
f:= proc(n) local L,i,p; L:= [seq(ithprime(i),i=1..n)]: p:= convert(L,`*`); if n::even then if p mod convert(L,`+`) = 0 then return p else return 0 fi else do p:= convert(L,`*`); if p mod convert(L,`+`) = 0 then return p fi; if p > 10^225 then return FAIL fi; L:= [op(L[2..-1]),nextprime(L[-1])]; od fi; end proc: map(f, [$1..26]);
Comments