A021102 Decimal expansion of 1/98.

0, 1, 0, 2, 0, 4, 0, 8, 1, 6, 3, 2, 6, 5, 3, 0, 6, 1, 2, 2, 4, 4, 8, 9, 7, 9, 5, 9, 1, 8, 3, 6, 7, 3, 4, 6, 9, 3, 8, 7, 7, 5, 5, 1, 0, 2, 0, 4, 0, 8, 1, 6, 3, 2, 6, 5, 3, 0, 6, 1, 2, 2, 4, 4, 8, 9, 7, 9, 5, 9, 1, 8, 3, 6, 7, 3, 4, 6, 9, 3, 8, 7, 7, 5, 5, 1, 0, 2, 0, 4, 0, 8, 1, 6, 3, 2, 6, 5, 3

Offset

0,4

Comments

Generalization:

1/8 = sum (2^i/10^(i+1)), i >= 0,

1/98 = sum (2^i/100^(i+1)), i >= 0, (this sequence)

1/998 = sum (2^i/1000^(i+1)), i >= 0,

1/9998 = sum (2^i/10000^(i+1)), i >= 0, ... - Daniel Forgues, Oct 28 2011

Links

Table of n, a(n) for n=0..98.

Mario Raso, Integer Sequences in Cryptography: A New Generalized Family and its Application, Ph. D. Thesis, Sapienza University of Rome (Italy 2025). See p. 9.

Mario Raso and Daniele Venturi, On integer sequences in cryptography, J. Math. Cryptol. 20(1) (2026), Article 20240033.

Index entries for periodic sequences.

Index entries for linear recurrences with constant coefficients, signature (1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,-1,1).

Mathematica

Join[{0}, RealDigits[1/98, 10, 120][[1]]] (* Harvey P. Dale, May 29 2013 *)

Prog

(PARI) a(n)=if(n, 577839643763819597984422160356236180402015\10^(n%42)%10, 0) \\ Charles R Greathouse IV, May 28 2026

Crossrefs

Cf. A020821 (1/8), A022002 (1/998), A236799 (1/9998).

Sequence in context: A077966 A275670 A393242 * A021053 A182443 A128983

Adjacent sequences: A021099 A021100 A021101 * A021103 A021104 A021105

Keyword

nonn,cons,easy

Author

N. J. A. Sloane

Status

approved