A044379 Numbers n such that string 4,7 occurs in the base 10 representation of n but not of n-1.

47, 147, 247, 347, 447, 470, 547, 647, 747, 847, 947, 1047, 1147, 1247, 1347, 1447, 1470, 1547, 1647, 1747, 1847, 1947, 2047, 2147, 2247, 2347, 2447, 2470, 2547, 2647, 2747, 2847, 2947, 3047, 3147, 3247, 3347, 3447, 3470

Offset

1,1

Links

Table of n, a(n) for n=1..39.

Mathematica

Select[Range[4000], MemberQ[Partition[IntegerDigits[#], 2, 1], {4, 7}] && !MemberQ[Partition[IntegerDigits[#-1], 2, 1], {4, 7}]&] (* Harvey P. Dale, Nov 29 2012 *)

Crossrefs

Sequence in context: A040984 A136070 A055822 * A044760 A142505 A047948

Adjacent sequences: A044376 A044377 A044378 * A044380 A044381 A044382

Keyword

nonn,base

Author

Clark Kimberling

Status

approved