A241143 Numbers n such that n and 7n share at least one digit.

5, 10, 13, 15, 16, 17, 18, 19, 20, 21, 25, 26, 29, 30, 31, 32, 33, 34, 35, 39, 40, 42, 43, 45, 49, 50, 51, 53, 55, 60, 64, 65, 66, 67, 68, 70, 71, 75, 80, 83, 84, 85, 86, 90, 95, 96, 97, 98, 99, 100, 101, 102, 103, 105, 107, 110, 113, 115, 116, 117, 118, 120, 123, 125, 126, 128, 129, 130, 131, 132, 133, 134, 135, 139, 140

Offset

1,1

Comments

All numbers n which are congruent to 0 (mod 5) have this characteristic.

Links

Table of n, a(n) for n=1..75.

Example

13 is in the sequence since 13 and 7*13 = 91 and together they share the digit 1.

Mathematica

fQ[n_] := Intersection[ IntegerDigits[ n], IntegerDigits[7 n]] != {}; Select[ Range[ 100], fQ]

Crossrefs

Cf. A129845, A129846, A129848, A241141, A241142, A241144, A241145, A241146.

Sequence in context: A313377 A224448 A046130 * A073503 A313378 A226386

Adjacent sequences: A241140 A241141 A241142 * A241144 A241145 A241146

Keyword

base,easy,nonn

Author

Robert G. Wilson v, Apr 16 2014

Status

approved