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Integers that have exactly one representation as a sum of two or more consecutive primes.
4

%I #23 Feb 16 2025 08:32:49

%S 5,8,10,12,15,17,18,23,24,26,28,30,31,39,42,48,49,52,53,56,58,59,67,

%T 68,71,75,77,78,84,88,95,97,98,101,102,109,121,124,127,128,129,131,

%U 132,139,144,150,155,156,158,159,160,161,162,168,169,172,173,181,184,186,192

%N Integers that have exactly one representation as a sum of two or more consecutive primes.

%C More fundamental than A050936, which gives integers having 1 *or more* such representations

%H T. D. Noe, <a href="/A084146/b084146.txt">Table of n, a(n) for n=1..10000</a>

%H Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/PrimeSums.html">Prime Sums</a>

%F A084143(a(n)) = 1. - _Ray Chandler_, Sep 20 2023

%p # uses code of A084143

%p isA084146 := proc(n::integer)

%p if A084143(n) = 1 then

%p true;

%p else

%p false;

%p end if;

%p end proc:

%p for n from 1 to 300 do

%p if isA084146(n) then

%p printf("%d,",n) ;

%p end if;

%p end do: # _R. J. Mathar_, Aug 19 2020

%Y Cf. A050936, A084143, A337095 (subset of primes).

%K nonn,changed

%O 1,1

%A _Eric W. Weisstein_, May 15 2003

%E More terms from _Matthew Conroy_, May 25 2003