A245426 Number of nonnegative integers with property that their base 7/4 expansion (see A024641) has n digits.

7, 7, 14, 21, 42, 70, 126, 217, 378, 665, 1162, 2037, 3563, 6237, 10913, 19096, 33418, 58485, 102347, 179109, 313439, 548520, 959910, 1679839, 2939720, 5144510, 9002889, 15755061, 27571355, 48249873, 84437276, 147765233, 258589156, 452531023, 791929292

Offset

1,1

Links

Table of n, a(n) for n=1..35.

Example

The numbers 7-13 are represented by 40, 41, 42, 43, 44, 45, 46 respectively in base 7/4. These are the only integers with two digits, and so a(2)=7.

Prog

(Sage)
A=[1]
for i in [1..60]:
    A.append(ceil((7-4)/4*sum(A)))
[7*x for x in A]

Crossrefs

Cf. A024641, A081848.

Sequence in context: A112438 A309459 A022090 * A168379 A179886 A214829

Adjacent sequences: A245423 A245424 A245425 * A245427 A245428 A245429

Keyword

nonn,base

Author

James Van Alstine, Jul 21 2014

Status

approved