Jake L Lande - cp's OEIS frontend

User: Jake L Lande

Jake L Lande has authored 2 sequences.

A375214 Odd numbers with equal numbers of even and odd digits.

21, 23, 25, 27, 29, 41, 43, 45, 47, 49, 61, 63, 65, 67, 69, 81, 83, 85, 87, 89, 1001, 1003, 1005, 1007, 1009, 1021, 1023, 1025, 1027, 1029, 1041, 1043, 1045, 1047, 1049, 1061, 1063, 1065, 1067, 1069, 1081, 1083, 1085, 1087, 1089, 1201, 1203, 1205, 1207, 1209, 1221, 1223, 1225

Offset: 1

Jake L Lande, Aug 07 2024

Numbers with an odd length cannot be in this sequence.

			1001 is odd and has two even digits (0,0) and two odd digits (1,1).

Jake L Lande, Table of n, a(n) for n = 1..1000

Subsequence of A227870.

Complement of A375213 within A227870.

filter:= proc(n) local L;
  L:= convert(n,base,10);
  nops(select(type,L,even))=nops(L)/2
end proc:
select(filter, [seq(seq(i,i=10^(d-1)+1 .. 10^d, 2),d=2..4,2)]); # Robert Israel, Aug 07 2024

eeo[n_] := (id = IntegerDigits[n]; Count[EvenQ@id, True] == Count[OddQ@id, True]); Select[Select[Range[1225], eeo], Mod[#, 2] == 1 &]

A375213 Even numbers with equal numbers of even and odd digits.

Original entry on oeis.org

10, 12, 14, 16, 18, 30, 32, 34, 36, 38, 50, 52, 54, 56, 58, 70, 72, 74, 76, 78, 90, 92, 94, 96, 98, 1010, 1012, 1014, 1016, 1018, 1030, 1032, 1034, 1036, 1038, 1050, 1052, 1054, 1056, 1058, 1070, 1072, 1074, 1076, 1078, 1090, 1092, 1094, 1096, 1098, 1100

Offset: 1

Jake L Lande, Aug 05 2024

Numbers with an odd digit length cannot be in this sequence.

			1010 is even and has two even digits (0,0) and two odd digits (1,1).

Jake L Lande, Table of n, a(n) for n = 1..1000

Subsequence of A227870 and hence A001637.

Complement of A375214 within A227870.

eeo[n_] := (id = IntegerDigits[n]; Count[EvenQ@id, True] == Count[OddQ@id, True]); Select[Select[Range[1100], eeo], Mod[#, 2] == 0 &]

cp's OEIS Frontend

User: Jake L Lande

A375214 Odd numbers with equal numbers of even and odd digits.

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