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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.

A343070 a(1) = 1, for n > 1, a(n) is the smallest positive integer for which a(n-1) + n + a(n) is a prime.

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%I A343070 #11 Apr 30 2021 23:04:37
%S A343070 1,2,2,1,1,4,2,1,1,2,4,1,3,2,2,1,1,4,6,3,5,2,4,1,3,2,2,1,1,6,4,1,3,4,
%T A343070 2,3,1,2,2,1,1,4,6,3,5,2,4,1,3,6,2,5,1,4,2,1,1,2,6,1,5,4,4,3,3,2,2,1,
%U A343070 1,2,6,1,5,4,4,3,3,2,2,1,1,6,8
%N A343070 a(1) = 1, for n > 1, a(n) is the smallest positive integer for which a(n-1) + n + a(n) is a prime.
%H A343070 Todor Szimeonov, <a href="https://newprimax.blogspot.com/2021/04/a-completive-sequence.html">A completive sequence</a>
%t A343070 a[1] = 1; a[n_] := a[n] = NextPrime[a[n - 1] + n] - a[n - 1] - n; Array[a, 100] (* _Amiram Eldar_, Apr 04 2021 *)
%o A343070 (Python)
%o A343070 from sympy import nextprime
%o A343070 def aupton(terms):
%o A343070   alst = [1]
%o A343070   for n in range(2, terms+1):
%o A343070     alst.append(nextprime(alst[-1] + n) - alst[-1] - n)
%o A343070   return alst
%o A343070 print(aupton(87)) # _Michael S. Branicky_, Apr 04 2021
%Y A343070 Cf. A343039.
%K A343070 nonn
%O A343070 1,2
%A A343070 _Todor Szimeonov_, Apr 04 2021