%N Numbers whose name in German contains the letter Ö (O with Umlaut).
%C These are the numbers whose decimal expansion contains the substring "12", with the '2' being the i-th digit for some i with i modulo 3 = 1 and the least significant digit having index 1.
%C These are the numbers whose names contain 'twelve' in English.
%e 612 is 'sechshundertzwölf' in German, containing the letter Ö. Therefore 612 is a term of the sequence.
%Y Cf. A208934.
%A _Felix Fröhlich_, Dec 19 2015