OFFSET
1,3
COMMENTS
By the conjecture in A257317, any positive integer should be the sum of two distinct terms of the current sequence one of which is even.
LINKS
Zhi-Wei Sun, Table of n, a(n) for n = 1..10000
Zhi-Wei Sun, Natural numbers represented by floor(x^2/a) + floor(y^2/b) + floor(z^2/c), arXiv:1504.01608 [math.NT], 2015.
EXAMPLE
a(1) = 0 since {9*0+3*2-1,9*0+3*2+1} = {5,7} is a twin prime pair.
a(2) = 1 since {9*1+3*1-1,9*1+3*1+1} = {11,13} is a twin prime pair.
a(3) = 2 since {9*2+3*0-1,9*2+3*0+1} = {17,19} is a twin prime pair.
MATHEMATICA
TQ[m_]:=PrimeQ[3m-1]&&PrimeQ[3m+1]
PQ[m_]:=TQ[3*m]||TQ[3*m+1]||TQ[3*m+2]
n=0; Do[If[PQ[m], n=n+1; Print[n, " ", m]], {m, 0, 340}]
CROSSREFS
KEYWORD
nonn
AUTHOR
Zhi-Wei Sun, Apr 25 2015
STATUS
approved