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

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

1,3

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.

Links

Jaroslav Krizek, Table of n, a(n) for n = 1..1023 (complete list)

Example

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.

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 *)

Prog

(Magma) A257128:=func<n | exists(r){k: k in [1..100000] | Seqint(Setseq(Set(Sort(&cat[Intseq(k)])))) eq n} select r else 0>; [A257128(n): n in[A009995(n)]]

Crossrefs

Cf. A000027, A009995, A227362.

Sequence in context: A375755 A210538 A247143 * A339541 A247808 A247807

Adjacent sequences: A257125 A257126 A257127 * A257129 A257130 A257131

Keyword

nonn,base,fini,full

Author

Jaroslav Krizek, Apr 16 2015

Status

approved