A121528 a(1)=1. a(n) = n-th integer from among those positive integers which are coprime to the sum of the previous terms of this sequence.

1, 2, 4, 4, 5, 11, 10, 8, 16, 10, 11, 23, 29, 27, 17, 31, 18, 18, 27, 41, 21, 43, 24, 24, 32, 26, 50, 30, 29, 61, 31, 101, 41, 81, 35, 107, 37, 113, 42, 42, 41, 83, 76, 44, 67, 91, 58, 85, 97, 79, 151, 64, 61, 211, 57, 139, 57, 135, 59, 131, 103, 135, 63, 159, 65, 197, 71

Offset

1,2

Links

Table of n, a(n) for n=1..67.

Example

45 = the sum of the terms a(1) to a(8), 45 = 1+2+4+4+5+11+10+8. 1,2,4,7,8,11,13,14,16,17... are the positive integers which are coprime to 45. 16 is the 9th of these integers, so a(9) = 16.

Prog

(PARI) {m=67; print1(1, ", "); s=1; for(n=2, m, k=n; c=0; while(k>0, c++; if(gcd(s, c)==1, k--)); print1(c, ", "); s=s+c)} - (Klaus Brockhaus, Aug 15 2006)

Crossrefs

Cf. A121527.

Sequence in context: A261393 A366541 A327629 * A243003 A223227 A160904

Adjacent sequences: A121525 A121526 A121527 * A121529 A121530 A121531

Keyword

nonn

Author

Leroy Quet, Aug 05 2006

Extensions

More terms from Klaus Brockhaus, Aug 15 2006

Status

approved