

A080854


Numbers which can be expressed as the sum of two distinct primes in exactly five ways.


6



48, 54, 64, 70, 76, 104, 106, 118, 124, 134, 136, 146, 148, 164, 166, 188
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OFFSET

1,1


COMMENTS

Apparently there are no further terms beyond 188.  R. J. Mathar, Oct 01 2021


LINKS

Table of n, a(n) for n=1..16.


FORMULA

{j: A117929(j) = 5} .  R. J. Mathar, Oct 01 2021


EXAMPLE

54 is a term as 54 = 31 + 23 = 37 + 17 = 41 + 13 = 43 + 11 = 47 + 7 are only the five ways to express 54 as a sum of two distinct primes.


MAPLE

P:=proc(q, w) local a, k, n;
for n from 1 to q do a:=0; for k from 1 to trunc(n/2) do
if isprime(k) and isprime(nk) and n<>2*k then a:=a+1; fi; od;
if a=w then print(n); fi; od; end: P(200, 5); # Paolo P. Lava, May 21 2014


CROSSREFS

Cf. A077914 (2 ways), A077969 (3 ways), A078299 (4 ways), A080862 (6 ways).
Sequence in context: A258694 A328738 A067191 * A255267 A345503 A259037
Adjacent sequences: A080851 A080852 A080853 * A080855 A080856 A080857


KEYWORD

nonn


AUTHOR

Shyam Sunder Gupta, Mar 29 2003


STATUS

approved



