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A166685
Odd numbers that are the sum of two consecutive nonprimes.
3
1, 5, 17, 19, 29, 31, 41, 43, 49, 51, 53, 55, 65, 67, 69, 71, 77, 79, 89, 91, 97, 99, 101, 103, 109, 111, 113, 115, 125, 127, 129, 131, 137, 139, 149, 151, 153, 155, 161, 163, 169, 171, 173, 175, 181, 183, 185, 187, 189, 191, 197, 199, 209, 211, 221, 223, 229
OFFSET
1,2
LINKS
EXAMPLE
a(1)=0(1st nonprime)+1(2nd nonprime)=1(odd);
a(2)=1(2nd nonprime)+4(3rd nonprime)=5(odd).
MATHEMATICA
Select[Total/@Partition[Select[Range[0, 200], !PrimeQ[#]&], 2, 1], OddQ] (* Harvey P. Dale, Mar 07 2020 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
EXTENSIONS
Entries checked by R. J. Mathar, Apr 24 2010
STATUS
approved