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A036301
Numbers whose sum of even digits and sum of odd digits are equal.
34
0, 112, 121, 134, 143, 156, 165, 178, 187, 211, 314, 336, 341, 358, 363, 385, 413, 431, 516, 538, 561, 583, 615, 633, 651, 718, 781, 817, 835, 853, 871, 1012, 1021, 1034, 1043, 1056, 1065, 1078, 1087, 1102, 1120, 1201, 1210, 1223, 1232, 1245, 1254, 1267, 1276, 1289, 1298
OFFSET
1,2
FORMULA
This set A036301 = { n | A071650(n) = 0 }. - M. F. Hasler, Aug 11 2023
MATHEMATICA
Select[Range[0, 10000], Plus @@Select[IntegerDigits[ # ], OddQ]\[Equal]Plus @@Select[IntegerDigits[ # ], EvenQ]&] (* Zak Seidov, Feb 17 2005 *)
PROG
(Magma) [ n: n in [0..1300] | (#A eq 0 select 0 else &+A) eq (#B eq 0 select 0 else &+B) where A is [ d: d in D | IsOdd(d) ] where B is [ d: d in D | IsEven(d) ] where D is Intseq(n) ];
(PARI) select( is_A036301(n)=!vecsum(apply(t->(-1)^t*t, digits(n))), [0..1999]) \\ This defines the function is_A036301 = !A071650; the surrounding select(...) just serves as a check and illustration. - M. F. Hasler, Dec 09 2018
A36301=[112]; A036301(n, L=#A36301)={while(n>L, A36301=concat(A36301, next_A036301(A36301[L], L, L+=1))); A36301[n]} \\ M. F. Hasler, Aug 11 2023
next_A036301(N, L=#A36301, k=setsearch(A36301, N+1, 1)) = if(k>L, until( is_A036301(N+=1), ); N, k, A36301[k], N+1) \\ next larger term: min { a(k) > N }. - M. F. Hasler, Aug 11 2023
(Python)
def eodiff(n):
digs = list(map(int, str(n)))
return abs(sum(d for d in digs if d%2==0)-sum(d for d in digs if d%2==1))
def aupto(lim): return [m for m in range(lim+1) if eodiff(m) == 0]
print(aupto(1298)) # Michael S. Branicky, Feb 21 2021
CROSSREFS
Cf. A071650 (sum of odd digits minus sum of even digits).
Sequence in context: A096680 A109383 A281926 * A117723 A359142 A329719
KEYWORD
nonn,base
AUTHOR
Patrick De Geest, Dec 15 1998
EXTENSIONS
Zero added by Zak Seidov, Nov 22 2010
Name edited by Michel Marcus, Jan 14 2021
STATUS
approved