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%I #12 Sep 08 2022 08:46:19
%S 7,77,78,79,87,97,777,778,779,787,788,789,797,798,799,877,878,879,887,
%T 897,977,978,979,987,997,7777,7778,7779,7787,7788,7789,7797,7798,7799,
%U 7877,7878,7879,7887,7888,7889,7897,7898,7899,7977,7978,7979,7987,7988,7989
%N Numbers whose smallest decimal digit is 7.
%C Numbers n such that A054054(n) = 7.
%C Prime terms are in A106107.
%t Select[Range[8000], Min[IntegerDigits[#]] == 7 &] (* _Giovanni Resta_, Mar 23 2017 *)
%o (Magma) [n: n in [1..100000] | Minimum(Setseq(Set(Sort(&cat[Intseq(n)])))) eq 7]
%o (PARI) isok(n) = vecmin(digits(n)) == 7; \\ _Michel Marcus_, Mar 25 2017
%Y Cf. Sequences of numbers whose smallest decimal digit is k (for k = 0..9): A011540 (k = 0), A284062 (k = 1), A284063 (k = 2), A284064 (k = 3), A284065 (k = 4), A284066 (k = 5), A284067 (k = 6), this sequence (k = 7), A284069 (k = 8), A002283 (k = 9).
%K nonn,base
%O 1,1
%A _Jaroslav Krizek_, Mar 23 2017
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