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 A307056 #13 Mar 25 2019 04:20:33 %S A307056 1,1,0,2,0,1,0,0,1,1,0,2,0,0,2,2,0,4,0,0,1,0,0,0,1,0,1,0,1,1,0,0,1,3, %T A307056 0,0,2,0,0,0,2,0,2,0,2,2,0,0,3,1,0,0,4,0,0,0,4,1,1,0,4,4,0,0,6,0,0,0, %U A307056 6,2,0,0,1,0,0,0,0,1,0,1,0,0,1,1,0,0,0,1,1,2,2,0,1,2,3,0,0,1,5,0,0,0,1,5,4 %N A307056 Row n = digits of A025487(n) in primorial base. %C A307056 A025487 is the sequence of products of primorials (A002110). %H A307056 Michael De Vlieger, <a href="/A307056/b307056.txt">Table of n, a(n) for n = 1..10122</a>, (rows 1 <= n <= 1200, flattened). %H A307056 Michael De Vlieger, <a href="/A307056/a307056.txt">Relation of A307056 with A025487, A002110, and A067255</a>. %e A307056 First rows of this sequence: %e A307056 n A025487(n) Row n %e A307056 ------------------------------- %e A307056 1 1 1 %e A307056 2 2 1, 0 %e A307056 3 4 2, 0 %e A307056 4 6 1, 0, 0 %e A307056 5 8 1, 1, 0 %e A307056 6 12 2, 0, 0 %e A307056 7 16 2, 2, 0 %e A307056 8 24 4, 0, 0 %e A307056 9 30 1, 0, 0, 0 %e A307056 10 32 1, 0, 1, 0 %e A307056 11 36 1, 1, 0, 0 %e A307056 12 48 1, 3, 0, 0 %e A307056 13 60 2, 0, 0, 0 %e A307056 14 64 2, 0, 2, 0 %e A307056 15 72 2, 2, 0, 0 %e A307056 16 96 3, 1, 0, 0 %e A307056 17 120 4, 0, 0, 0 %e A307056 18 128 4, 1, 1, 0 %e A307056 19 144 4, 4, 0, 0 %e A307056 20 180 6, 0, 0, 0 %e A307056 21 192 6, 2, 0, 0 %e A307056 22 210 1, 0, 0, 0, 0 %e A307056 ... %t A307056 f[n_] := {{1}}~Join~Block[{lim = Product[Prime@ i, {i, n}], ww = NestList[Append[#, 1] &, {1}, n - 1], dec}, dec[x_] := Apply[Times, MapIndexed[Prime[First@ #2]^#1 &, x]]; Map[Block[{w = #, k = 1}, Sort@ Prepend[If[Length@ # == 0, #, #[[1]]], Product[Prime@ i, {i, Length@ w}] ] &@ Reap[Do[If[# < lim, Sow[#]; k = 1, If[k >= Length@ w, Break[], k++]] &@ dec Set[w, If[k == 1, MapAt[# + 1 &, w, k], PadLeft[#, Length@ w, First@ #] &@ Drop[MapAt[# + Boole[i > 1] &, w, k], k - 1] ]], {i, Infinity}] ][[-1]] ] &, ww]]; Block[{nn = 10, b}, b = MixedRadix[Reverse@ Prime@ Range@ nn]; Map[IntegerDigits[#, b] &, Union@ Flatten@ f@ nn]] %Y A307056 Cf. A002110, A002182, A025487. %K A307056 nonn,base,tabf %O A307056 1,4 %A A307056 _Michael De Vlieger_, Mar 21 2019