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A112825 Least even number k such that the Goldbach gap is 2n, or 0 if no such number exists. 3
4, 10, 14, 24, 22, 26, 36, 34, 50, 52, 46, 60, 58, 70, 62, 80, 78, 74, 84, 82, 86, 94, 100, 126, 114, 106, 120, 118, 130, 0, 138, 0, 134, 144, 142, 152, 158, 162, 176, 172, 166, 0, 178, 196, 0, 208, 198, 194, 204, 202, 230, 216, 214, 236, 0, 226, 0, 0, 0, 0, 258, 0, 254 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,1
LINKS
EXAMPLE
a(1)=10 because the two Goldbach partitions of 10 are {3,7} & {5,5} and (5-3)/2=1.
MATHEMATICA
f[n_] := Block[{p = 2, q = n/2}, While[ !PrimeQ[p] || !PrimeQ[n - p], p++ ]; While[ !PrimeQ[q] || !PrimeQ[n - q], q-- ]; q - p]; t = Table[0, {100}]; Do[a = f[2n]; If[a < 100 && t[[a/2 + 1]] == 0, t[[a/2 + 1]] = 2n; Print[{2a, 2n}]], {n, 2, 10^4}]; Take[t, 63]
CROSSREFS
Cf. A020481.
Sequence in context: A175731 A242486 A060031 * A051741 A022382 A162521
KEYWORD
nonn
AUTHOR
Robert G. Wilson v, Sep 05 2005
STATUS
approved

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Last modified April 14 07:58 EDT 2024. Contains 371655 sequences. (Running on oeis4.)