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 A008570 #24 Mar 23 2025 03:56:38 %S A008570 1,9,8,1,7,2,9,6,5,6,1,5,9,0,4,9,5,3,1,4,4,1,4,7,8,2,9,6,9,4,3,0,4,6, %T A008570 7,2,1,3,8,7,4,2,0,4,8,9,3,4,8,6,7,8,4,4,0,1,3,1,3,8,1,0,5,9,6,0,9,2, %U A008570 8,2,4,2,9,5,3,6,4,8,1,2,5,4,1,8,6,5,8,2,8,3,2,9,2,2,8,7,6,7,9 %N A008570 Digits of powers of 9. %C A008570 The constant whose decimal expansion is this sequence is irrational (Mahler, 1981). - _Amiram Eldar_, Mar 23 2025 %H A008570 Seiichi Manyama, <a href="/A008570/b008570.txt">Rows n = 0..100, flattened</a> %H A008570 Kurt Mahler, <a href="https://doi.org/10.1016/0022-314X(81)90010-X">On some irrational decimal fractions</a>, Journal of Number Theory, Vol. 13, No. 2 (1981), pp. 268-269. %e A008570 Triangle begins: %e A008570 1; %e A008570 9; %e A008570 8, 1; %e A008570 7, 2, 9; %e A008570 6, 5, 6, 1; %e A008570 5, 9, 0, 4, 9; %e A008570 5, 3, 1, 4, 4, 1; %e A008570 4, 7, 8, 2, 9, 6, 9; %e A008570 ... %t A008570 Flatten[IntegerDigits/@(9^Range[0,20])] (* _Harvey P. Dale_, Nov 17 2024 *) %Y A008570 Cf. A001019. %Y A008570 Cf. A000455, A008564, A008565, A008566, A008567, A008568, A008569, A008571, A008572, A008573, A010054. %K A008570 nonn,base,easy,tabf %O A008570 0,2 %A A008570 _N. J. A. Sloane_