A072630 Values of n where A072629 switches from 01010.. into 0000.. or back.

1, 7, 19, 53, 147, 403, 1095, 2979, 8103, 22025, 59873, 162753, 442413, 1202603, 3269017, 8886109, 24154951, 65659969, 178482299, 485165195, 1318815733, 3584912845, 9744803445, 26489122129, 72004899337, 195729609427

Offset: 1

Author

Labos Elemer, Jun 28 2002

Keywords

• nonn

Crossrefs

See also A004648, A072608, A072609, A072610, A072630.

Programs

Mathematica

m[x_] := Mod[x*Floor[Log[x]//N],2]; Do[s=m[n]+m[n+1]; s1=m[n+1]+m[n+2]; If[ !Equal[s1,s],Print[n]],{n,1,1000000}]

Formula

See program below.

a(n) = A000149(n) or A000149(n)-1 whichever is odd. [From Max Alekseyev, Feb 06 2010]

Extensions

More terms from Max Alekseyev, Feb 06 2010