A353438 Integers m such that the decimal expansion of 1/m contains the digit 2.

4, 5, 7, 8, 13, 14, 16, 17, 19, 23, 28, 29, 31, 32, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 56, 57, 58, 59, 61, 62, 64, 67, 68, 69, 70, 71, 76, 77, 78, 79, 80, 81, 82, 83, 85, 86, 87, 89, 92, 93, 94, 95, 97, 98, 102, 103, 105, 106, 107, 108, 109

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..71.

Example

m = 8 is a term since 1/8 = 0.125.
m = 44 is a term since 1/44 = 0.022727272727... (here, 2 is the smallest digit).
m = 495 is a term since 1/495 = 0.002020202... (here, 2 is the largest digit).

Mathematica

f[n_] := Union[ Flatten[ RealDigits[ 1/n][[1]] ]]; Select[ Range@ 125, MemberQ[f@#, 2] &]

Crossrefs

A341383 (largest digit=2) and A352156 (smallest digit=2) are subsequences.

Similar with digit k: A352154 (k=0), A353437 (k=1), this sequence (k=2), A353439 (k=3), A353440 (k=4), A353441 (k=5), A353442 (k=6), A353443 (k=7), A353444 (k=8), A333237 (k=9).

Sequence in context: A240161 A023629 A331840 * A033164 A276324 A226628

Adjacent sequences: A353435 A353436 A353437 * A353439 A353440 A353441

Keyword

nonn,base

Author

Bernard Schott and Robert G. Wilson v, Apr 22 2022

Status

approved