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 A377784 #8 Nov 19 2024 17:32:04 %S A377784 0,4,0,4,4,2,2,4,8,0,8,4,0,4,6,6,3,5,4,3,5,4,6,8,6,0,4,4,4,12,4,8,0, %T A377784 10,2,8,4,4,7,5,4,8,4,2,2,12,12,4,4,2,6,2,10,8,4,6,2,7,5,0,10,14,4,3, %U A377784 5,12,6,10,2,6,4,8,7,5,4,8,8,4,8,8,3,9,4,4 %N A377784 First-differences of A377783 (least nonsquarefree number > prime(n)). %C A377784 There are no consecutive 0's. %C A377784 Does this sequence contain every positive integer > 1? %t A377784 Differences[Table[NestWhile[#+1&,Prime[n],SquareFreeQ[#]&],{n,100}]] %Y A377784 Positions of 0's are A068361. %Y A377784 The opposite for squarefree is A378038, differences of A112925. %Y A377784 For prime-power instead of nonsquarefree and primes + 1 we have A377703, first-differences of A345531. %Y A377784 First-differences of A377783, union A378040. %Y A377784 The opposite is A378034 (differences of A378032), restriction of A378036 (differences A378033). %Y A377784 For squarefree instead of nonsquarefree we have A378037, first-differences of A112926. %Y A377784 Restriction of A378039 (first-differences of A120327) to the primes. %Y A377784 A000040 lists the primes, differences A001223, seconds A036263. %Y A377784 A005117 lists the squarefree numbers. %Y A377784 A013929 lists the nonsquarefree numbers, differences A078147, seconds A376593. %Y A377784 A061398, A068360, A337030, A377430, A377431 count squarefree numbers between primes. %Y A377784 A061399, A068361, A378086 count nonsquarefree numbers between primes. %Y A377784 A070321 gives the greatest squarefree number up to n. %Y A377784 Cf. A000015, A013928, A053797, A053806, A072284, A224363. %Y A377784 Cf. A377047, A377048, A377049. %Y A377784 Cf. A378082, A378083, A378084. %K A377784 nonn %O A377784 1,2 %A A377784 _Gus Wiseman_, Nov 18 2024