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.
%I A284065 #14 Sep 08 2022 08:46:19
%S A284065 4,44,45,46,47,48,49,54,64,74,84,94,444,445,446,447,448,449,454,455,
%T A284065 456,457,458,459,464,465,466,467,468,469,474,475,476,477,478,479,484,
%U A284065 485,486,487,488,489,494,495,496,497,498,499,544,545,546,547,548,549,554
%N A284065 Numbers whose smallest decimal digit is 4.
%C A284065 Numbers n such that A054054(n) = 4.
%C A284065 Prime terms are in A106104.
%t A284065 With[{k = 4}, Select[Range@ 554, And[Total@ Take[#, k] == 0, #[[k + 1]] > 0] &@ RotateRight@ DigitCount@ # &]] (* _Michael De Vlieger_, Mar 20 2017 *)
%t A284065 (* or *)
%t A284065 Select[Range[1000], Min[IntegerDigits[#]] == 4 &] (* _Giovanni Resta_, Mar 22 2017 *)
%o A284065 (Magma) [n: n in [1..100000] | Minimum(Setseq(Set(Sort(&cat[Intseq(n)])))) eq 4]
%o A284065 (PARI) isok(n) = vecmin(digits(n)) == 4; \\ _Michel Marcus_, Mar 25 2017
%Y A284065 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), this sequence (k = 4), A284066 (k = 5), A284067 (k = 6), A284068 (k = 7), A284069 (k = 8), A002283 (k = 9).
%K A284065 nonn,base
%O A284065 1,1
%A A284065 _Jaroslav Krizek_, Mar 19 2017