A118684 Numbers k for which the Mertens function M(k) (A002321) is 1.

1, 94, 97, 98, 99, 100, 146, 147, 148, 161, 162, 215, 216, 230, 237, 330, 334, 337, 338, 349, 350, 351, 352, 365, 394, 397, 399, 400, 415, 416, 418, 538, 539, 540, 542, 606, 794, 799, 800, 801, 806, 809, 810, 813, 815, 816, 822, 851, 852, 870, 874, 875

Offset: 1

Author

Yoav Kallus (colonelmustard(AT)gmail.com), May 20 2006

Keywords

• nonn

Examples

			M(94) = Sum_{n=1..94} mu(n) = 1.
		

Links

• Seiichi Manyama, Table of n, a(n) for n = 1..10000
• Eric Weisstein's World of Mathematics, Mertens Function

Crossrefs

Numbers k such that M(k) = b: A171395 (b=-12), A171394 (b=-11), A171393 (b=-10), A171392 (b=-9), A171391 (b=-8), A171383 (b=-7), A171374 (b=-6), A171236 (b=-5), A171235 (b=-4), A171098 (b=-3), A171097 (b=-2), A171096 (b=-1), A028442 (b=0), this sequence (b=1), A171403 (b=2), A171404 (b=3), A171406 (b=4), A171427 (b=5), A171428 (b=6), A171436 (b=7).

Cf. A002321, A051400.

Programs

Mathematica

Select[Range[500], Plus @@ MoebiusMu[Range[#]] == 1 &] (* Carl Najafi, Aug 17 2011 *)

PARI

isok(n) = sum(k=1, n, moebius(k)) == 1; \\ Michel Marcus, Nov 20 2017