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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A329407 Among the pairwise sums of any five consecutive terms there is exactly one prime sum; lexicographically earliest such sequence of distinct positive numbers.

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%I A329407 #33 Feb 09 2020 15:58:09
%S A329407 1,2,7,8,13,12,14,4,20,21,6,18,15,10,3,17,5,11,16,25,9,19,23,30,26,32,
%T A329407 22,33,24,27,28,36,29,34,35,40,31,41,37,44,38,43,39,42,45,46,47,48,49,
%U A329407 68,51,57,54,53,61,58,62,50,52,59,56,60,55,67,63,65,66,69,75,77,64,71,70,72,73,76,74,80
%N A329407 Among the pairwise sums of any five consecutive terms there is exactly one prime sum; lexicographically earliest such sequence of distinct positive numbers.
%H A329407 Jean-Marc Falcoz, <a href="/A329407/b329407.txt">Table of n, a(n) for n = 1..10000</a>
%e A329407 a(1) = 1 by minimality.
%e A329407 a(2) = 2 as 2 is the smallest available integer not leading to a contradiction. Note that as 1 + 2 = 3 we already have our prime sum.
%e A329407 a(3) = 7 as a(3) = 3, 4, 5 or 6 would produce at least one prime sum too many.
%e A329407 a(4) = 8 as a(4) = 3, 4, 5 or 6 would again produce at least one prime sum too many.
%e A329407 a(5) = 13 as a(5) = 3, 4, 5, 6, 9, 10, 11 or 12 would also produce at least one prime sum too many.
%e A329407 a(6) = 12 and we have the single prime sum we need among the last 5 integers {2,7,8,13,12}, which is 19 = 12 + 7.
%e A329407 And so on.
%Y A329407 Cf. A329333 (3 consecutive terms, exactly 1 prime sum).
%Y A329407 Cf. A329405: no prime among the pairwise sums of 3 consecutive terms.
%Y A329407 Cf. A329406 .. A329410: exactly 1 prime sum using 4, ..., 10 consecutive terms.
%Y A329407 Cf. A329411 .. A329416: exactly 2 prime sums using 3, ..., 10 consecutive terms.
%Y A329407 See also A329450, A329452 onwards for "nonnegative" variants.
%K A329407 nonn
%O A329407 1,2
%A A329407 _Eric Angelini_ and _Jean-Marc Falcoz_, Nov 13 2019