A076588 First occurrence of n as a term in the continued fraction for Pi/4.

2, 8, 3, 76, 17, 67, 50, 54, 11, 20, 73, 413, 59, 162, 7, 75, 13, 587, 393, 24, 112, 228, 403, 40, 843, 560, 590, 69, 187, 617, 215, 400, 1182, 259, 1680, 548, 758, 226, 133, 78, 1265, 589, 96, 169, 3108, 5892, 258, 261, 4608, 3810, 2386, 1251, 2698, 2374

Offset: 1

Author

Benoit Cloitre, Oct 20 2002

Keywords

• base
• nonn
• changed

Crossrefs

Cf. A032523, A070989.

Programs

Mathematica

With[{cf=ContinuedFraction[Pi/4,6000]},Table[Position[cf,n,1,1],{n,60}]]//Flatten (* Harvey P. Dale, Aug 25 2025 *)

PARI

\\ 15000 precision digits
v=contfrac(Pi/4); a(n)=if(n<0,0,s=1; while(abs(n-component(v,s))>0,s++); s)