Additive primes: Difference between revisions

=={{header|FreeBASIC}}==

As with the other special primes tasks, use one of the primality testing algorithms as an include.

<lang freebasic>#include "isprime.bas"

function digsum( n as uinteger ) as uinteger

dim as uinteger s

while n

s+=n mod 10

n\=10

wend

return s

end function

dim as uinteger s

print "Prime","Digit Sum"

for i as uinteger = 2 to 499

if isprime(i) then

s = digsum(i)

if isprime(s) then

print i, s

end if

end if

next i</lang>

{{out}}

<pre style="height:16em">Prime Digit Sum

2 2

3 3

5 5

7 7

11 2

23 5

29 11

41 5

43 7

47 11

61 7

67 13

83 11

89 17

101 2

113 5

131 5

137 11

139 13

151 7

157 13

173 11

179 17

191 11

193 13

197 17

199 19

223 7

227 11

229 13

241 7

263 11

269 17

281 11

283 13

311 5

313 7

317 11

331 7

337 13

353 11

359 17

373 13

379 19

397 19

401 5

409 13

421 7

443 11

449 17

461 11

463 13

467 17

487 19</pre>