A353443 Integers m such that the decimal expansion of 1/m contains the digit 7.

7, 13, 14, 17, 19, 21, 23, 27, 28, 29, 34, 35, 36, 37, 38, 43, 44, 46, 47, 49, 51, 52, 53, 56, 57, 58, 59, 61, 63, 67, 68, 69, 70, 71, 76, 77, 79, 81, 83, 84, 85, 86, 87, 89, 92, 93, 94, 95, 97, 98, 102, 103, 107, 109, 112, 113, 114, 115, 116, 117, 118, 119, 121, 122, 126, 127

Offset: 1

Author

Bernard Schott and Robert G. Wilson v, Apr 25 2022

Keywords

• nonn

Comments

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

Examples

			m = 7 is a term since 1/7 = 0.142857142857...
m = 27 is a term since 1/27 = 0.037037037... (here, 7 is the largest digit).
		

Links

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

Crossrefs

A351473 (largest digit=7) is a subsequence.

Similar with digit k: A352154 (k=0), A353437 (k=1), A353438 (k=2), A353439 (k=3), A353440 (k=4), A353441 (k=5), A353442 (k=6), this sequence (k=7), A353444 (k=8), A333237 (k=9).

Programs

Mathematica

f[n_] := Union[ Flatten[ RealDigits[ 1/n][[1]] ]]; Select[ Range@ 150, MemberQ[f@#, 7] &]