MAIN    START
        LAD     GR1,0
        LAD     GR2,0           ; インデックス
BEGIN   CPA     GR2,CNT
        JZE     FIN
        LAD     GR3,SEQ,GR2
        AND     GR2,GR2
        CPA     GR2,=1
        JPL     SUMP2
        LD      GR1,GR2
        JUMP    STSEQ
SUMP2   LD      GR1,-2,GR3
        ADDA    GR1,-1,GR3
STSEQ   ST      GR1,0,GR3
        LAD     GR2,1,GR2
        JUMP    BEGIN
FIN     RET
CNT     DC      10
SEQ     DS      10
        END