login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A353437
Integers m such that the decimal expansion of 1/m contains the digit 1.
7
1, 6, 7, 8, 9, 10, 14, 17, 19, 21, 23, 24, 26, 28, 29, 31, 32, 34, 35, 38, 39, 43, 46, 47, 49, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100
OFFSET
1,2
COMMENTS
If m is a term, 10*m is also a term, so terms with no trailing zeros are all primitive terms.
EXAMPLE
m = 7 is a term since 1/7 = 0.142857142857... (here, 1 is the smallest digit).
m = 17 is a term since 1/17 = 0.05882352941176470588235294117647...
m = 99 is a term since 1/99 = 0.0101010101... (here, 1 is the largest digit).
MATHEMATICA
f[n_] := Union[ Flatten[ RealDigits[ 1/n][[1]] ]]; Select[ Range@ 125, MemberQ[f@#, 1] &]
CROSSREFS
A333402 (largest digit=1) and A352155 (smallest digit=1) are subsequences.
Similar with digit k: A352154 (k=0), this sequence (k=1), A353438 (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: A067901 A115840 A371565 * A352155 A058368 A321852
KEYWORD
base,nonn
AUTHOR
STATUS
approved