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A062096
a(1) = 2; for n > 1, a(n) is smallest number, greater than a(n-1), which is relatively prime to the sum of all previous terms.
0
2, 3, 4, 5, 9, 10, 13, 15, 16, 17, 19, 20, 22, 23, 25, 26, 27, 29, 31, 33, 34, 35, 37, 38, 39, 41, 43, 45, 46, 47, 49, 50, 51, 53, 56, 57, 59, 60, 61, 63, 64, 65, 67, 68, 69, 71, 72, 73, 75, 76, 79, 81, 83, 85, 86, 88, 89, 95, 96, 97, 101, 102, 103, 107, 108, 109, 113, 114
OFFSET
1,1
EXAMPLE
After 5 the next term is 9 as 2 + 3 + 4 + 5 = 14 and 6, 7 and 8 have common divisors with 14.
MAPLE
a[1]:=2: for m from 2 to 80 do b:=proc(n) if gcd(sum(a[j], j=1..m-1), n)=1 then n else fi end: M:=[seq(b(n), n=a[m-1]+1..200)]: a[m]:=M[1] od:seq(a[n], n=1..80); # Emeric Deutsch, Jul 18 2005
PROG
(PARI) first(n) = my(v = vector(n), s, t); s = v[1] = 2; for(i = 2, n, t=v[i-1]+1; while(gcd(t, s)!=1, t++); v[i]=t; s+=v[i]); v \\ David A. Corneth, Aug 11 2017
CROSSREFS
Sequence in context: A015837 A262511 A075177 * A360687 A176008 A143827
KEYWORD
nonn,easy
AUTHOR
Amarnath Murthy, Jun 19 2001
EXTENSIONS
Corrected and extended by Emeric Deutsch, Jul 18 2005
STATUS
approved