cp's OEIS Frontend

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.

A257128 a(n) = the smallest number k such that A227362(k) = A009995(n).

Original entry on oeis.org

0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 20, 12, 30, 13, 23, 40, 14, 24, 34, 50, 15, 25, 35, 45, 60, 16, 26, 36, 46, 56, 70, 17, 27, 37, 47, 57, 67, 80, 18, 28, 38, 48, 58, 68, 78, 90, 19, 29, 39, 49, 59, 69, 79, 89, 102, 103, 203, 123, 104, 204, 124, 304, 134, 234
Offset: 1

Views

Author

Jaroslav Krizek, Apr 16 2015

Keywords

Comments

A227362(n) = reverse concatenation of distinct digits of n in base 10, A009995(n) = possible values of A227362(m) in increasing order.
Finite sequence with 1023 terms.

Examples

			a(15) = 13 because 13 is the smallest number k such that reverse concatenation of distinct digits of k (i.e., 31) in base 10 = A227362(k) = A227362(13) = A009995(15) = 31.
		

Crossrefs

Programs

  • Magma
    A257128:=func; [A257128(n): n in[A009995(n)]]
  • Mathematica
    f[n_] := Block[{s = Sort@ Flatten@ Table[FromDigits /@ Subsets[Range[9, 0, -1], {j}], {j, 10}], i, k}, Reap@For[i = 1, i <= n, i++, k = 0; While[FromDigits[Reverse@ Union@ IntegerDigits@ k] != s[[i]], k++]; Sow@ k] // Flatten // Rest]; f@ 65 (* Michael De Vlieger, Apr 16 2015, after Zak Seidov at A009995, corrected by Robert G. Wilson v *)