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A340817 a(n) is the least prime of the form prime(n)*p + prime(n+1)*q + prime(n+2)*r where p,q,r are consecutive primes. 2

%I

%S 83,127,167,2749,257,307,1427,431,769,1811,617,4261,2843,2633,881,

%T 1459,2087,5023,6199,1831,3461,1373,1459,8353,1567,1607,1657,8353,

%U 8867,4111,4231,11801,20983,3529,4903,34283,5227,5399,7307,13103,18311,2917,2957,6311,15101,5113,3407,3457,19433,3581,23689

%N a(n) is the least prime of the form prime(n)*p + prime(n+1)*q + prime(n+2)*r where p,q,r are consecutive primes.

%H Robert Israel, <a href="/A340817/b340817.txt">Table of n, a(n) for n = 2..10000</a>

%F a(n) = prime(n)*A340821(n) + prime(n+1)*A151800(A340821(n)) + prime(n+2)*A151800(A151800(A340821(n))).

%e a(3) = 5*3 + 7*5 + 11*7 = 167.

%p f:= proc(n) local k,t;

%p for k from 1 do

%p t:=ithprime(n)*ithprime(k) + ithprime(n+1)*ithprime(k+1) + ithprime(n+2)*ithprime(k+2);

%p if isprime(t) then return t fi;

%p od

%p end proc:

%p map(f, [$2..30]);

%Y Cf. A151800, A340821.

%K nonn

%O 2,1

%A _J. M. Bergot_ and _Robert Israel_, Jan 22 2021

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Last modified October 18 03:25 EDT 2021. Contains 348065 sequences. (Running on oeis4.)