A062920 Numbers k that, when expressed in base 4 and then interpreted in base 5, give a multiple of k.
0, 1, 2, 3, 1060, 2137, 3197, 3214, 3217, 3337, 313259, 313406, 730473, 2304689, 2416087, 3579260, 28850251, 31289731, 132716102, 206771980, 530864408, 616417140, 621776006, 1553684761, 2123457632, 2232402380, 5264756497, 8929609520, 22137774186, 2543308829640
Offset: 1
Examples
3 in base 4 is 3, which interpreted in base 5 is 3 = 1*3.
Programs
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Mathematica
Join[{0},Select[Range[5000000],Divisible[FromDigits[IntegerDigits[#,4],5], #]&]] (* Harvey P. Dale, Dec 10 2012 *) -
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
Extensions
More terms from Naohiro Nomoto, Aug 06 2001
Offset corrected by and a(17)-a(30) from Giovanni Resta, Jun 28 2018