A043506 Numbers having two 4's in base 10.

44, 144, 244, 344, 404, 414, 424, 434, 440, 441, 442, 443, 445, 446, 447, 448, 449, 454, 464, 474, 484, 494, 544, 644, 744, 844, 944, 1044, 1144, 1244, 1344, 1404, 1414, 1424, 1434, 1440, 1441, 1442, 1443, 1445, 1446, 1447, 1448

Offset

1,1

Links

Daniel Starodubtsev, Table of n, a(n) for n = 1..10000

Mathematica

Select[Range[100000], DigitCount[#, 10, 4] == 2 &] (* Vincenzo Librandi, Nov 20 2015 *)

Prog

(PARI) c(k, d, b) = {my(c=0, f); while (k>b-1, f=k-b*(k\b); if (f==d, c++); k\=b); if (k==d, c++); return(c)}
for(n=0, 2000, if(c(n, 4, 10)==2, print1(n, ", "))) \\ Altug Alkan, Nov 20 2015

Crossrefs

Cf. A043498.

Subsequence of A011534.

Sequence in context: A358818 A183642 A183634 * A044376 A102438 A044757

Adjacent sequences: A043503 A043504 A043505 * A043507 A043508 A043509

Keyword

nonn,base

Author

Clark Kimberling

Status

approved