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A178041 Number of ways to represent the n-th prime (which has a nonzero number of such representations) as the sum of 4 distinct primes. 1

%I

%S 1,2,3,3,5,6,6,6,8,10,13,14,13,18,21,17,21,30,21,32,23,37,27,45,35,34,

%T 54,43,60,61,67,44,52,55,79,58,89,57,92,100,111,69,119,76,83,122,91,

%U 89,94,102,147,146,106,159,116,176,125,190,119,195,202,136,230,148,154,222

%N Number of ways to represent the n-th prime (which has a nonzero number of such representations) as the sum of 4 distinct primes.

%H Eric W. Weisstein, <a href="http://mathworld.wolfram.com/GoldbachConjecture.html">Goldbach Conjecture</a>,

%e a(1) = 1 because 17 = 2+3+5+7 is the unique solution for the smallest such prime.

%e a(2) = 2 because 23 = 2+3+5+13 = 2+3+7+11 are the only two solutions for the 2nd smallest such prime.

%e a(3) = 3 because 29 = 2+3+5+19 = 2+3+7+17 = 2+3+11+13 are the only 3 solutions for the 3rd smallest such prime.

%e a(4) = 3 because 31 = 2+3+7+19 = 2+5+7+17 = 2+5+11+13 are the only 3 solutions for the 4th smallest such prime.

%e a(5) = 5 because 37 = 2+3+13+19 = 2+5+7+23 = 2+5+11+19 = 2+5+13+17 = 2+7+11+17 are the only 5 solutions for the 5th smallest such prime.

%Y Cf. A000040, A038609 (sum of 2 distinct primes), A124867 (sum of 3 distinct primes), A124868 (not the sum of 3 distinct primes), A124884 (not the sum of n distinct primes).

%K easy,nonn

%O 1,2

%A _Jonathan Vos Post_, May 17 2010

%E Extended by _Zak Seidov_

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Last modified March 7 19:49 EST 2021. Contains 341931 sequences. (Running on oeis4.)