

A094747


Rearrangement of odd primes so that absolute successive differences are the least distinct even numbers. Priority is given to the least successive difference that has not occurred earlier.


2



3, 5, 11, 7, 17, 29, 37, 23, 41, 61, 83, 67, 43, 71, 97, 127, 163, 131, 89, 137, 103, 59, 19, 73, 13, 79, 149, 199, 251, 307, 269, 223, 281, 349, 277, 353, 431, 367, 293, 373, 311, 229, 313, 227, 139, 47, 151, 241, 337, 239, 347, 449, 563, 463, 557, 673, 797, 691, 809
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OFFSET

1,1


COMMENTS

We interpret the definition as saying that we find a(n+1) from a(n) by testing a(n)+2*d (first the minus, then the plus, d=1,2,3,4...., d not used before) for primality and for not already being on the list. This creates a list of odd primes, but there is no proof (yet) that all odd primes are in the sequence.  R. J. Mathar, Jul 29 2007


LINKS

Table of n, a(n) for n=1..59.


MAPLE

A094747 := proc(nmax) local a, diffs, d; a := [3] ; diffs := {} ; while nops(a) < nmax do d := 2 ; while true do if isprime(op(1, a)d) and not op(1, a)d in a and not abs(d) in diffs then a := [op(a), op(1, a)d] ; diffs := diffs union {d} ; break ; elif isprime(op(1, a)+d) and not op(1, a)+d in a and not abs(d) in diffs then a := [op(a), op(1, a)+d] ; diffs := diffs union {d} ; break ; else d := d+2 ; fi ; od ; od; RETURN(a) ; end: A094747(100) ; # R. J. Mathar, Jul 29 2007


CROSSREFS

Cf. A094748.
Sequence in context: A225487 A145398 A087322 * A300783 A287939 A129738
Adjacent sequences: A094744 A094745 A094746 * A094748 A094749 A094750


KEYWORD

nonn


AUTHOR

Amarnath Murthy, May 24 2004


EXTENSIONS

More terms from R. J. Mathar, Jul 29 2007


STATUS

approved



