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 A361825 #10 Mar 31 2023 06:55:57 %S A361825 1,2,4,5,6,8,3,10,12,9,14,16,7,18,20,15,22,24,21,26,28,25,30,32,27,34, %T A361825 36,33,38,40,35,42,44,39,46,48,45,50,52,55,54,56,51,58,60,57,62,64,65, %U A361825 66,68,63,70,72,69,74,76,49,78,80,75,82,84,81,86,88,85,90,92,87,94,96,93,98,100,95 %N A361825 a(1) = 1, a(2) = 2; for n > 2, a(n) is the smallest positive number that has not yet appeared that is a multiple of the smallest prime that does not divide a(n-2) + a(n-1). %C A361825 The sequence is conjectured to be a permutation of the positive integers, although it takes many terms for the primes to appear, e.g., a(191443) = 19. %H A361825 Scott R. Shannon, <a href="/A361825/a361825.png">Image of the first 50000 terms</a>. The green line is a(n) = n. %e A361825 a(3) = 4 as a(1) + a(2) = 1 + 2 = 3 which does not contain 2 as a prime factor, and 4 is the smallest unused number that is a multiple of 2. %e A361825 a(4) = 5 as a(2) + a(3) = 2 + 4 = 6 = 2*3 which does not contain 5 as a prime factor, and 5 is the smallest unused number that is a multiple of 5. %Y A361825 Cf. A351495, A359804, A353026, A352793. %K A361825 nonn %O A361825 1,2 %A A361825 _Scott R. Shannon_, Mar 25 2023