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A303788 a(n) = Sum_{i=0..m} d(i)*5^i, where Sum_{i=0..m} d(i)*6^i is the base-6 representation of n.

%I A303788 #41 Jun 29 2019 01:39:09
%S A303788 0,1,2,3,4,5,5,6,7,8,9,10,10,11,12,13,14,15,15,16,17,18,19,20,20,21,
%T A303788 22,23,24,25,25,26,27,28,29,30,25,26,27,28,29,30,30,31,32,33,34,35,35,
%U A303788 36,37,38,39,40,40,41,42,43,44,45,45,46,47,48,49,50,50,51,52,53,54,55
%N A303788 a(n) = Sum_{i=0..m} d(i)*5^i, where Sum_{i=0..m} d(i)*6^i is the base-6 representation of n.
%H A303788 Seiichi Manyama, <a href="/A303788/b303788.txt">Table of n, a(n) for n = 0..10000</a>
%e A303788 16 = 24_6, so a(16) = 2*5 + 4 = 14.
%e A303788 17 = 25_6, so a(17) = 2*5 + 5 = 15.
%e A303788 18 = 30_6, so a(18) = 3*5 + 0 = 15.
%e A303788 19 = 31_6, so a(19) = 3*5 + 1 = 16.
%o A303788 (Ruby)
%o A303788 def f(k, ary)
%o A303788   (0..ary.size - 1).inject(0){|s, i| s + ary[i] * k ** i}
%o A303788 end
%o A303788 def A(k, n)
%o A303788   (0..n).map{|i| f(k, i.to_s(k + 1).split('').map(&:to_i).reverse)}
%o A303788 end
%o A303788 p A(5, 100)
%o A303788 (PARI) a(n) = fromdigits(digits(n, 6), 5); \\ _Michel Marcus_, May 02 2018
%Y A303788 Sum_{i=0..m} d(i)*b^i, where Sum_{i=0..m} d(i)*(b+1)^i is the base (b+1) representation of n: A065361 (b=2), A215090 (b=3), A303787 (b=4), this sequence (b=5), A303789 (b=6).
%Y A303788 Cf. A037465.
%K A303788 nonn,base
%O A303788 0,3
%A A303788 _Seiichi Manyama_, Apr 30 2018