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A121640 a(1) = 1. a(n) = a(n-1) + (n-th integer from among those positive integers which are coprime to a(n-1)). 1
1, 3, 7, 11, 16, 27, 37, 45, 61, 71, 82, 105, 134, 161, 178, 209, 227, 245, 272, 313, 334, 377, 401, 425, 457, 483, 533, 563, 592, 653, 684, 785, 826, 907, 942, 1049, 1086, 1199, 1241, 1283, 1324, 1407, 1483, 1527, 1594, 1685, 1743, 1828, 1925, 2004, 2155, 2219 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..52.

PROG

(PARI) {m=52; print1(b=1, ", "); for(n=2, m, k=n; c=0; while(k>0, c++; if(gcd(b, c)==1, k--)); print1(a=b+c, ", "); b=a)} - (Klaus Brockhaus, Aug 14 2006)

CROSSREFS

Cf. A121641, A121047.

Sequence in context: A131024 A053982 A118000 * A319258 A112786 A023211

Adjacent sequences:  A121637 A121638 A121639 * A121641 A121642 A121643

KEYWORD

nonn

AUTHOR

Leroy Quet, Aug 12 2006

EXTENSIONS

More terms from Klaus Brockhaus, Aug 14 2006

STATUS

approved

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Last modified September 17 03:42 EDT 2021. Contains 347478 sequences. (Running on oeis4.)