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%I #12 Apr 18 2023 09:43:47
%S 0,1,2,3,33,219,840,1055,4220,16880,95322,178500,714000,981540,
%T 1387680,7676775,7924262,12418476,12419535,16552116,19188717,44591130,
%U 66079524,77842213,178364520,294607851,363167196,610436322,823488858,950204780
%N Numbers k that, when expressed in base 4 and then interpreted in base 7, give a multiple of k.
%e 33 in base 4 is 201, which interpreted in base 7 is 99 = 3*33.
%t Select[Range[0,20*10^6],Divisible[FromDigits[IntegerDigits[#,4],7],#]&] (* _Harvey P. Dale_, Nov 22 2015 *)
%K base,nonn
%O 1,3
%A _Erich Friedman_, Jul 21 2001
%E More terms from _Naohiro Nomoto_, Aug 06 2001
%E Offset changed to 1 and a(22)-a(30) from _Georg Fischer_, Mar 13 2023