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 A262353 #33 Sep 08 2022 08:46:14 %S A262353 8,764,76394,7639321,763932023,76393202251,7639320225003, %T A262353 763932022500211,76393202250021031,7639320225002103036, %U A262353 763932022500210303591,76393202250021030359083,7639320225002103035908264,763932022500210303590826332,76393202250021030359082633127 %N A262353 a(n) = ceiling((3-sqrt(5))*10^(2*n+1)). %C A262353 a(n) is a special family of 2nd-order base-10 grafting integers, because every integer generated by ceiling((3-sqrt(5))*10^(2*n+1)) is a grafting integer. %C A262353 A grafting number is a number whose digits, represented in base b, appear before or directly after the decimal point of its r-th root. Numbers of the simplest type deal with square roots in the decimal system. %C A262353 The constant x = 3-sqrt(5) is a solution of the general grafting equation (x*b^a)^(1/r) = x + c with corresponding values r = 2, b = 10, a = 1, c = 2 (where r >= 2 is the grafting root, b >= 2 is the base in which the numbers are represented, a >= 0 is the number of places the decimal point is shifted, and c >= 0 is the constant added to the front of the result). %D A262353 Matt Parker, Things to make and do in the Fourth Dimension, New York (Ferrar, Strauss and Giroux), 2014, p. 62-63. %F A262353 a(n) = ceiling((3-sqrt(5))*10^(2*n+1)). %e A262353 sqrt(8) = 2.828427..., %e A262353 sqrt(764) = 27.6405..., %e A262353 sqrt(76394) = 276.39464... %p A262353 Digits:=2000: a:=n->ceil((3-sqrt(5))*10^(2*n+1)); seq(a(n),n=0..14); %t A262353 Table[Ceiling[(3 - Sqrt@ 5) 10^(2 n + 1)], {n, 14}] (* _Michael De Vlieger_, Mar 24 2016 *) %o A262353 (PARI) a(n) = ceil((3-sqrt(5))*10^(2*n+1)); \\ _Altug Alkan_, Mar 24 2016 %o A262353 (PARI) a(n) = 30*100^n - sqrtint(10^(4*n+2)*5) \\ _Charles R Greathouse IV_, Jan 20 2017 %o A262353 (Magma) [Ceiling((3-Sqrt(5))*10^(2*n+1)):n in [0..14]]; // _Marius A. Burtea_, Aug 08 2019 %Y A262353 Subsequence of A232087. %Y A262353 Cf. A187799. %K A262353 nonn,base %O A262353 0,1 %A A262353 _Martin Renner_, Mar 24 2016 %E A262353 a(0) = 8 prepended by _Robert Tanniru_, Aug 06 2019