A353440 Integers m such that the decimal expansion of 1/m contains the digit 4.

7, 14, 17, 19, 21, 22, 23, 24, 25, 26, 28, 29, 31, 34, 35, 38, 39, 41, 43, 46, 47, 49, 51, 53, 56, 57, 58, 59, 61, 62, 65, 67, 68, 69, 70, 71, 76, 79, 81, 83, 84, 85, 86, 87, 89, 92, 93, 94, 95, 96, 97, 98, 102, 103, 104, 106, 107, 109, 112, 113, 114, 115, 116, 117, 118

Offset

1,1

Comments

If m is a term, 10*m is also a term, so terms with no trailing zeros are all primitive terms.

Links

Table of n, a(n) for n=1..65.

Index entries for sequences related to decimal expansion of 1/n.

Example

m = 14 is a term since 1/14 = 0.0714285714285...
m = 22 is a term since 1/22 = 0.04545454545... (here, 4 is the smallest digit).
m = 693 is a term since 1/693 = 0.001443001443... (here, 4 is the largest digit).

Mathematica

f[n_] := Union[ Flatten[ RealDigits[ 1/n][[1]] ]]; Select[ Range@ 125, MemberQ[f@#, 4] &

Crossrefs

A351470 (largest digit=4) and A352158 (smallest digit=4) are subsequences.

Similar with digit k: A352154 (k=0), A353437 (k=1), A353438 (k=2), A353439 (k=3), this sequence (k=4), A353441 (k=5), A353442 (k=6), A353443 (k=7), A353444 (k=8), A333237 (k=9).

Sequence in context: A167197 A336797 A100599 * A198390 A118905 A254064

Adjacent sequences: A353437 A353438 A353439 * A353441 A353442 A353443

Keyword

nonn,base

Author

Bernard Schott and Robert G. Wilson v, Apr 24 2022

Status

approved