|
%I #15 Jun 28 2018 06:22:57
%S 0,1,2,3,1060,2137,3197,3214,3217,3337,313259,313406,730473,2304689,
%T 2416087,3579260,28850251,31289731,132716102,206771980,530864408,
%U 616417140,621776006,1553684761,2123457632,2232402380,5264756497,8929609520,22137774186,2543308829640
%N Numbers k that, when expressed in base 4 and then interpreted in base 5, give a multiple of k.
%e 3 in base 4 is 3, which interpreted in base 5 is 3 = 1*3.
%t Join[{0},Select[Range[5000000],Divisible[FromDigits[IntegerDigits[#,4],5], #]&]] (* _Harvey P. Dale_, Dec 10 2012 *)
%o (PARI) baseE(x, b)= { local(d, e, f); e=0; f=1; while (x>0, d=x-b*(x\b); x\=b; e+=d*f; f=f*10); return(e) } baseI(x, b)= { local(d, e, f); e=0; f=1; while (x>0, d=x-10*(x\10); x\=10; e+=d*f; f=f*b); return(e) } { n=-1; for (m=0, 10^9, x=baseI(baseE(m, 4), 5); if (x%m == 0, write("b062920.txt", n++, " ", m); if (n==15, break)) ) } \\ _Harry J. Smith_, Aug 13 2009
%Y Cf. A062921, A062922, A062923, A032540.
%K base,nonn
%O 1,3
%A _Erich Friedman_, Jul 21 2001
%E More terms from _Naohiro Nomoto_, Aug 06 2001
%E Offset corrected by and a(17)-a(30) from _Giovanni Resta_, Jun 28 2018
|
