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.
%I A358530 #18 Sep 22 2024 02:29:48 %S A358530 13,19,31,41,43,61,71,73,83,101,103,109,131,139,151,167,181,193,199, %T A358530 227,229,241,257,271,281,283,311,313,337,349,373,383,401,421,433,443, %U A358530 461,463,487,491,503,523,547,563,571,593,601,617,619,641,643,661,677 %N A358530 a(n) = n-th prime prime(k) such that prime(k) - prime(k-1) < prime(k-1) - prime(k-2). %C A358530 This sequence, together with A358528 and A181424, partition the set of primes >= 5. The corresponding sequences of indices, A358531, A358529, and A356347, partition the set of positive integers >= 3. %F A358530 a(n) = A151800(A051634(n)). - _Andrew Howroyd_, Sep 21 2024 %e A358530 n 1 2 3 4 5 6 7 %e A358530 k 6 8 11 13 14 18 20 %e A358530 prime(n) 13 19 31 41 43 61 71 %t A358530 t = Select[2 + Range[140], %t A358530 Prime[#] - Prime[# - 1] < Prime[# - 1] - Prime[# - 2] &] (* A358531 *) %t A358530 Prime[t] (* A358530 *) %Y A358530 Cf. A001223, A051634, A079419, A358528, A358529, A358531, A181424, A356347. %K A358530 nonn,easy %O A358530 1,1 %A A358530 _Clark Kimberling_, Nov 21 2022 %E A358530 Incorrect formula removed by _Georg Fischer_, Sep 21 2024