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 A215074 #9 Jul 22 2025 23:21:10 %S A215074 1,1,2,4,12,40,154,660,3113,15893,86857,502092,3036032,19006591, %T A215074 122119857,799665333,5308126648,35576413852,240063646519,1627605038848 %N A215074 Number of squarefree words of length n in an 8-ary alphabet, with new values 0..7 introduced in increasing order. %C A215074 Column 7 of A215075. %e A215074 Some solutions for n=9: %e A215074 ..0....0....0....0....0....0....0....0....0....0....0....0....0....0....0....0 %e A215074 ..1....1....1....1....1....1....1....1....1....1....1....1....1....1....1....1 %e A215074 ..2....2....2....2....2....2....2....2....2....2....2....2....2....2....2....2 %e A215074 ..3....0....1....3....1....3....3....1....3....3....0....3....1....1....3....0 %e A215074 ..4....3....3....4....3....4....4....3....4....0....3....4....3....3....4....3 %e A215074 ..0....1....1....5....4....5....1....0....2....2....4....5....4....0....0....4 %e A215074 ..3....4....0....4....0....4....5....4....5....4....5....6....0....1....1....0 %e A215074 ..1....2....4....0....2....1....3....2....0....5....1....7....5....0....0....5 %e A215074 ..2....0....1....6....3....2....0....5....1....4....6....2....1....3....5....2 %K A215074 nonn %O A215074 1,3 %A A215074 _R. H. Hardin_ Aug 02 2012