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A147882 Positive integers k that are balanced, meaning that if k has d digits, then its initial ceiling(d/2) digits have the same sum as its last ceiling(d/2) digits.

%I A147882 #24 Oct 06 2023 10:47:27
%S A147882 1,2,3,4,5,6,7,8,9,11,22,33,44,55,66,77,88,99,101,111,121,131,141,151,
%T A147882 161,171,181,191,202,212,222,232,242,252,262,272,282,292,303,313,323,
%U A147882 333,343,353,363,373,383,393,404,414,424,434,444,454,464,474,484,494
%N A147882 Positive integers k that are balanced, meaning that if k has d digits, then its initial ceiling(d/2) digits have the same sum as its last ceiling(d/2) digits.
%C A147882 Differs from A110751 in cases like n=1010, 1089, 1102, 1120, 1203, 1212, 1230, etc. - _R. J. Mathar_, Dec 13 2008
%H A147882 David A. Corneth, <a href="/A147882/b147882.txt">Table of n, a(n) for n = 1..10000</a> (first 6649 terms from Jason Tarver)
%H A147882 Project Euler, <a href="http://projecteuler.net/index.php?section=problems&amp;id=217">Problem 217: Balanced Numbers</a>.
%e A147882 From _David A. Corneth_, Sep 28 2023: (Start)
%e A147882 353 is a term as it has k = 3 digits and so we see that the sum of the first ceiling(k/2) = ceiling(3/2) = 2 and the last ceiling(k/2) = ceiling(3/2) = 2 are equal and indeed 3 + 5 = 5 + 3.
%e A147882 13922 is a term as it has k = 5 digits and so we see that the sum of the first ceiling(k/2) = ceiling(5/2) = 2 and the last ceiling(k/2) = ceiling(5/2) = 2 are equal and indeed 1 + 3 + 9 = 9 + 2 + 2. (End)
%o A147882 (PARI) is(n) = {my(d = digits(n), qdp1 = #d + 1); sum(i = 1, #d\2, d[i]-d[qdp1 - i]) == 0} \\ _David A. Corneth_, Sep 28 2023
%Y A147882 Cf. A002113, A110751.
%K A147882 nonn,base
%O A147882 1,2
%A A147882 Jason Tarver (scottarver(AT)gmail.com), Nov 17 2008
%E A147882 Definition clarified by _N. J. A. Sloane_, Oct 06 2023