(In reply to
a few more by Steve Herman)
Indeed I had neglected that allowing negative numbers also allows duplicates of a given absolute value. There are 1852 ways altogether.
By power of 10 they are
power of 10 number
3 20
4 152
5 440
6 632
7 458
8 140
9 10
DEFDBL A-Z
DIM lct(25)
CLS
FOR a = -50 TO 45
IF a MOD 3 <> 0 AND a MOD 7 <> 0 AND a MOD 11 <> 0 AND a MOD 13 <> 0 THEN
FOR b = a + 1 TO 46
IF b MOD 3 <> 0 AND b MOD 7 <> 0 AND b MOD 11 <> 0 AND b MOD 13 <> 0 THEN
FOR c = b + 1 TO 47
IF c MOD 3 <> 0 AND c MOD 7 <> 0 AND c MOD 11 <> 0 AND c MOD 13 <> 0 THEN
abc = a * b * c
FOR d = c + 1 TO 48
IF d MOD 3 <> 0 AND d MOD 7 <> 0 AND d MOD 11 <> 0 AND d MOD 13 <> 0 THEN
FOR e = d + 1 TO 49
IF e MOD 3 <> 0 AND e MOD 7 <> 0 AND e MOD 11 <> 0 AND e MOD 13 <> 0 THEN
FOR f = e + 1 TO 50
IF f MOD 3 <> 0 AND f MOD 7 <> 0 AND f MOD 11 <> 0 AND f MOD 13 <> 0 THEN
prod = abc * d * e * f
s$ = LTRIM$(STR$(prod))
IF LEFT$(s$, 1) = "1" THEN
good = 1
FOR i = 2 TO LEN(s$)
IF MID$(s$, i, 1) <> "0" THEN good = 0: EXIT FOR
NEXT i
IF good THEN pow10 = LEN(s$) - 1: lct(pow10) = lct(pow10) + 1: ct = ct + 1: PRINT a; b; c; d; e; f, prod
END IF
END IF
NEXT f
END IF
NEXT e
END IF
NEXT d
END IF
NEXT c
END IF
NEXT b
END IF
NEXT a
FOR i = 0 TO 10: PRINT i, lct(i): NEXT
PRINT ct
|
|
Posted by Charlie
on 2013-08-05 22:17:25 |
re: a few more
