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Numbers whose smallest decimal digit is 1.
8

%I #22 Sep 08 2022 08:46:19

%S 1,11,12,13,14,15,16,17,18,19,21,31,41,51,61,71,81,91,111,112,113,114,

%T 115,116,117,118,119,121,122,123,124,125,126,127,128,129,131,132,133,

%U 134,135,136,137,138,139,141,142,143,144,145,146,147,148,149,151,152

%N Numbers whose smallest decimal digit is 1.

%C Numbers k such that A054054(k) = 1.

%C Prime terms are in A106101.

%t Select[Range[300], Min[IntegerDigits[#]]==1 &] (* _Indranil Ghosh_, Mar 19 2017 *)

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

%o (PARI) for(n=1, 300, if(vecmin(digits(n))==1, print1(n,", "))) \\ _Indranil Ghosh_, Mar 19 2017

%o (Python)

%o from sympy.ntheory.factor_ import digits

%o print([n for n in range(1, 301) if min(digits(n)[1:])==1]) # _Indranil Ghosh_, Mar 19 2017

%Y Cf. Sequences of numbers whose smallest decimal digit is k (for k = 0..9): A011540 (k = 0), this sequence (k = 1), A284063 (k = 2), A284064 (k = 3), A284065 (k = 4), A284066 (k = 5), A284067 (k = 6), A284068 (k = 7), A284069 (k = 8), A002283 (k = 9).

%K nonn,base

%O 1,2

%A _Jaroslav Krizek_, Mar 19 2017