A061546 Harmonic mean of digits is 7.

7, 77, 777, 7777, 77777, 777777, 3999999, 4688999, 4689899, 4689989, 4689998, 4698899, 4698989, 4698998, 4699889, 4699898, 4699988, 4868999, 4869899, 4869989, 4869998, 4886999, 4888888, 4889699, 4889969, 4889996, 4896899

Offset: 1

Author

Vladeta Jovovic, Jun 13 2001

Keywords

• base
• easy
• nonn

Examples

			6666999 is a term since 7/(1/6+1/6+1/6+1/6+1/9+1/9+1/9)=7.
		

Crossrefs

Cf. A062179-A062185, A061383-A061388, A061423-A061425.

Programs

Mathematica

Do[ h = IntegerDigits[n]; If[ Sort[h][[1]] != 0 && Length[h]/Apply[Plus, 1/h] == 7, Print[n]], {n, 1, 10^6}]

Extensions

More terms from Robert G. Wilson v, Aug 08 2001