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A249559 Same definition as A247665, except first term is 3. 1
3, 2, 5, 7, 4, 9, 11, 13, 17, 19, 8, 23, 15, 29, 31, 37, 41, 43, 47, 49, 53, 59, 16, 61, 67, 71, 25, 27, 73, 79, 83, 89, 97, 101, 103, 107, 109, 113, 121, 127, 91, 131, 137, 139, 149, 151, 32, 157, 163, 167, 173, 179, 181, 191, 85, 193, 57, 197, 199, 211, 223, 227, 229, 233, 239, 241, 251, 257, 263 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..69.

PROG

(Sage, from Nadia Heninger, Oct 28 2014: s is the starting point (2 in A247665, 3 here)).

def gen(s):

    sequence = [s]

    available = range(2, 2*s)

    available.pop(available.index(s))

    yield s

    while True:

        available.extend(range(available[-1]+1, next_prime(available[-1])+1))

        for i, e in enumerate(available):

            if all([gcd(e, sequence[j])==1 for j in range(-len(sequence)/2, 0)]):

                available.pop(i)

                sequence.append(e)

                yield(e)

                break

g = gen(3)

[g.next() for i in range(40)]  (gets first 40 terms)

CROSSREFS

Sequence in context: A105353 A115966 A203602 * A182846 A292962 A069196

Adjacent sequences:  A249556 A249557 A249558 * A249560 A249561 A249562

KEYWORD

nonn

AUTHOR

N. J. A. Sloane, Nov 02 2014

STATUS

approved

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Last modified September 22 20:30 EDT 2018. Contains 315270 sequences. (Running on oeis4.)