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A242561
a(0)=0; thereafter, a(n) is n multiplied by the distance of a(n-1) to the nearest prime.
0
0, 2, 0, 6, 4, 5, 0, 14, 8, 9, 20, 11, 0, 26, 42, 15, 32, 17, 0, 38, 20, 21, 44, 23, 0, 50, 78, 27, 56, 87, 60, 31, 0, 66, 34, 105, 72, 37, 0, 78, 40, 41, 0, 86, 132, 45, 92, 141, 96, 49, 100, 51, 104, 53, 0, 110, 56, 171, 116, 177
OFFSET
0,2
COMMENTS
It appears that any starting value a(0) will produce a sequence which merges with this one at some point.
Also, if we create a new sequence, call it b(n), from this one by changing one term, say a(k), then it appears that there exists an index m such that a(n)=b(n) for all n>=m. For example, if we replace a(10) by 1341, which is a number within the prime gap 1327-1361, then this new sequence has b(17)=a(17) and so the two sequences agree after that point. - J. M. Bergot, May 21 2014.
FORMULA
a(n+1) = n*A051699(a(n)), starting a(0)=0.
EXAMPLE
The sequence begins with a(0)=0, so |2-0|=2 and a(1)=1*2=2; find
the next m=|2-2|=0, so a(2)=0*2=0; find the next m=|2-0|=2, so a(3)=3*2=6; find the next m=|7-6|=1, so a(4)=1*4=4.
CROSSREFS
Sequence in context: A233207 A136656 A256850 * A372767 A131595 A290826
KEYWORD
nonn
AUTHOR
J. M. Bergot, May 17 2014
EXTENSIONS
Edited by N. J. A. Sloane, May 20 2014
STATUS
approved