A043518 Numbers having two 7's in base 10.

77, 177, 277, 377, 477, 577, 677, 707, 717, 727, 737, 747, 757, 767, 770, 771, 772, 773, 774, 775, 776, 778, 779, 787, 797, 877, 977, 1077, 1177, 1277, 1377, 1477, 1577, 1677, 1707, 1717, 1727, 1737, 1747, 1757, 1767, 1770, 1771

Offset: 1

Author

Clark Kimberling

Keywords

• nonn
• base

Links

• Daniel Starodubtsev, Table of n, a(n) for n = 1..10000

Crossrefs

Subsequence of A011537.

Programs

Mathematica

Select[Range[2000],DigitCount[#,10,7]==2&] (* Harvey P. Dale, Jul 30 2022 *)