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%I #26 Sep 08 2022 08:46:18
%S 7,17,27,37,47,57,67,70,71,72,73,74,75,76,77,107,117,127,137,147,157,
%T 167,170,171,172,173,174,175,176,177,207,217,227,237,247,257,267,270,
%U 271,272,273,274,275,276,277,307,317,327,337,347,357,367,370,371,372
%N Numbers n whose largest decimal digit is 7.
%C Numbers n such that A054055(n) = 7.
%C Number of terms less than 10^n is 8^n - 7^n.
%C Prime terms are in A106095.
%H Muniru A Asiru, <a href="/A283610/b283610.txt">Table of n, a(n) for n = 1..5000</a>
%t Select[Range[1000], Max[IntegerDigits[#]] == 7 &] (* _Giovanni Resta_, Mar 19 2017 *)
%o (Magma) [n: n in [1..100000] | Maximum(Setseq(Set(Sort(&cat[Intseq(n)])))) eq 7]
%o (PARI) for(n=1, 500, if(vecmax(digits(n))==7, print1(n,", "))) \\ _Indranil Ghosh_, Mar 19 2017
%o (Python)
%o from sympy.ntheory.factor_ import digits
%o [n for n in range(1, 401) if max(digits(n)[1:]) == 7] # _Indranil Ghosh_, Mar 19 2017
%o (GAP) Filtered([1..380],n->Maximum(ListOfDigits(n))=7); # _Muniru A Asiru_, Feb 27 2019
%Y Cf. A054055, A106095.
%Y Cf. Sequences of numbers n whose largest decimal digit is k (for k = 1 - 9): A007088 (k = 1), A277964 (k = 2), A277965 (k = 3), A277966 (k = 4), A283608 (k = 5), A283609 (k = 6), this sequence (k = 7), A283611 (k = 8), A011539 (k = 9).
%K nonn,base,easy
%O 1,1
%A _Jaroslav Krizek_, Mar 19 2017
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