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A353438
Integers m such that the decimal expansion of 1/m contains the digit 2.
7
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.
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
KEYWORD
nonn,base
AUTHOR
STATUS
approved