A019991 Indices n such that A307672(2*n) = 4.

10, 17, 28, 30, 31, 37, 44, 50, 51, 53, 64, 71, 82, 84, 85, 88, 90, 92, 93, 94, 100, 109, 111, 112, 118, 125, 131, 132, 134, 143, 149, 150, 151, 153, 155, 158, 159, 161, 172, 179, 190, 192, 193, 199, 206, 212, 213, 215, 226, 233, 244, 246, 247, 250

Offset: 0

Author

Bill Gosper

Keywords

• nonn

Comments

The original definition was: "A threequence, a 3-way partitioning of the integers: define a,b,c,A,B,C by a(0)=true, b(0)=c(0)=A(0)=B(0)=C(0)=false, a(n)=a(m) OR C(m) OR B(m), b(n)= b(m) OR A(m) OR C(m), c(n)= c(m) OR B(m) OR A(m), A(n)= A(m) OR b(m) OR c(m), B(n)= B(m) OR c(m) OR a(m), C(n)= C(m) OR a(m) OR b(m), where m = [ (n+1)/3 ]; sequence gives n such that c(2n) is true." - Sean A. Irvine, Apr 30 2019

Links

• R. W. Gosper, J. Z. Hunts, Strange Series for Sierpinski’s Gasket, G4G10 Exchange Book, Vol. 2 (2012), 59-60.

Crossrefs

Cf. A019989, A019990, A307672.

Extensions

More terms from Sean A. Irvine, Apr 15 2019

New name from Sean A. Irvine, Apr 30 2019