A284064 Numbers whose smallest decimal digit is 3.

3, 33, 34, 35, 36, 37, 38, 39, 43, 53, 63, 73, 83, 93, 333, 334, 335, 336, 337, 338, 339, 343, 344, 345, 346, 347, 348, 349, 353, 354, 355, 356, 357, 358, 359, 363, 364, 365, 366, 367, 368, 369, 373, 374, 375, 376, 377, 378, 379, 383, 384, 385, 386, 387, 388

Offset: 1

Author

Jaroslav Krizek, Mar 19 2017

Keywords

• nonn
• base

Comments

Numbers n such that A054054(n) = 3.

Prime terms are in A106103.

Links

• Robert Israel, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. Sequences of numbers whose smallest decimal digit is k (for k = 0..9): A011540 (k = 0), A284062 (k = 1), A284063 (k = 2), this sequence (k = 3), A284065 (k = 4), A284066 (k = 5), A284067 (k = 6), A284068 (k = 7), A284069 (k = 8), A002283 (k = 9).

Programs

Magma

[n: n in [1..100000] | Minimum(Setseq(Set(Sort(&cat[Intseq(n)])))) eq 3]

Maple

L[1]:= {3}: G[1]:= {$4..9}:
for n from 2 to 3 do L[n]:= map(t -> seq(10*t+j,j=3..9), L[n-1]) union map(t -> 10*t+3, G[n-1]);
  G[n]:= map(t -> seq(10*t+j,j=4..9), G[n-1])
od:
seq(op(sort(convert(L[n],list))),n=1..3); # Robert Israel, Mar 27 2017

Mathematica

With[{k = 3}, Select[Range@ 388, And[Total@ Take[#, k] == 0, #[[k + 1]] > 0] &@ RotateRight@ DigitCount@ # &]] (* Michael De Vlieger, Mar 20 2017 *) (* or *)
Select[Range[10000], Min[IntegerDigits[#]] == 3 &] (* faster, simpler, Giovanni Resta, Mar 22 2017 *)

PARI

isok(n) = vecmin(digits(n)) == 3; \\ Michel Marcus, Mar 25 2017