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A338827 For any number with decimal representation (d(1), d(2), ..., d(k)), the decimal representation of a(n) is (abs(d(1)-d(k)), abs(d(2)-d(k-1)), ..., abs(d(k)-d(1))).

%I A338827 #19 Nov 12 2020 16:43:35
%S A338827 0,0,0,0,0,0,0,0,0,0,11,0,11,22,33,44,55,66,77,88,22,11,0,11,22,33,44,
%T A338827 55,66,77,33,22,11,0,11,22,33,44,55,66,44,33,22,11,0,11,22,33,44,55,
%U A338827 55,44,33,22,11,0,11,22,33,44,66,55,44,33,22,11,0,11,22
%N A338827 For any number with decimal representation (d(1), d(2), ..., d(k)), the decimal representation of a(n) is (abs(d(1)-d(k)), abs(d(2)-d(k-1)), ..., abs(d(k)-d(1))).
%C A338827 Leading zeros are ignored.
%C A338827 All terms belong to A061917.
%H A338827 Rémy Sigrist, <a href="/A338827/b338827.txt">Table of n, a(n) for n = 0..10000</a>
%F A338827 a(n) = 0 iff n is a palindrome (A002113).
%F A338827 a(n) = A330240(n, A004086(n)).
%e A338827 For n = 1021:
%e A338827 - abs(1-1) = 0,
%e A338827 - abs(0-2) = 2,
%e A338827 - abs(2-0) = 2,
%e A338827 - abs(1-1) = 0,
%e A338827 - so a(1021) = 220.
%p A338827 a:= n-> (l-> (h-> add(h[j]*10^(j-1), j=1..nops(h)))([seq(
%p A338827     abs(l[i]-l[-i]), i=1..nops(l))]))(convert(n, base, 10)):
%p A338827 seq(a(n), n=0..70);  # _Alois P. Heinz_, Nov 12 2020
%o A338827 (PARI) a(n, base=10) = my (d=digits(n, base)); fromdigits(abs(d-Vecrev(d)), base)
%Y A338827 Cf. A002113, A004086, A056965, A061917, A175919 (binary analog), A330240, A338828 (ternary analog).
%K A338827 nonn,base,look,easy
%O A338827 0,11
%A A338827 _Rémy Sigrist_, Nov 11 2020