10 DEFINT A-Z: E=500
20 DIM P(E): P(0)=-1: P(1)=-1
30 FOR I=2 TO SQR(E)
40 IF NOT P(I) THEN FOR J=I*2 TO E STEP I: P(J)=-1: NEXT
50 NEXT
60 FOR I=B TO E: IF P(I) GOTO 100
70 J=I: S=0
80 IF J>0 THEN S=S+J MOD 10: J=J\10: GOTO 80
90 IF NOT P(S) THEN N=N+1: PRINT I,
100 NEXT
110 PRINT: PRINT N;" additive primes found below ";E