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A359123
First differences of A068811, halved.
2
1, 1, 2, 3, 6, 6, 3, 3, 3, 6, 6, 3, 4, 8, 12, 18, 3, 6, 18, 6, 9, 12, 18, 15, 3, 3, 12, 9, 15, 6, 18, 6, 9, 6, 18, 6, 15, 9, 12, 3, 3, 15, 18, 12, 9, 6, 18, 6, 3, 18, 12, 12, 9, 6, 3, 3, 9, 3, 3, 7, 17, 9, 51, 6, 9, 6, 12, 21, 21, 3, 6, 27, 27, 30, 6, 27, 9, 21, 12, 36, 84, 6
OFFSET
1,3
LINKS
MATHEMATICA
1/2*Differences@ Select[Prime@ Range[300], PrimeQ[10^(1 + Floor@ Log10[#]) - #] &] (* Michael De Vlieger, Dec 18 2022 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Dec 18 2022
STATUS
approved