Duffinian numbers: Difference between revisions

=={{header|MAD}}==

<syntaxhighlight lang="mad"> NORMAL MODE IS INTEGER

DIMENSION SIGMA(10000),OUTROW(10)

INTERNAL FUNCTION(AA,BB)

ENTRY TO GCD.

A = AA

B = BB

STEP WHENEVER A.E.B, FUNCTION RETURN A

WHENEVER A.G.B, A = A-B

WHENEVER A.L.B, B = B-A

TRANSFER TO STEP

END OF FUNCTION

INTERNAL FUNCTION(N)

ENTRY TO DUFF.

SIG = SIGMA(N)

FUNCTION RETURN SIG.G.N+1 .AND. GCD.(N,SIG).E.1

END OF FUNCTION

INTERNAL FUNCTION(N)

ENTRY TO TRIP.

FUNCTION RETURN DUFF.(N) .AND.

0 DUFF.(N+1) .AND. DUFF.(N+2)

END OF FUNCTION

THROUGH SZERO, FOR I=1, 1, I.G.10000

SZERO SIGMA(I) = 0

THROUGH SCALC, FOR I=1, 1, I.G.10000

THROUGH SCALC, FOR J=I, I, J.G.10000

SCALC SIGMA(J) = SIGMA(J) + I

PRINT COMMENT $ FIRST 50 DUFFINIAN NUMBERS$

CAND = 0

THROUGH DUFROW, FOR R=0, 1, R.GE.5

THROUGH DUFCOL, FOR C=0, 1, C.GE.10

SCHDUF THROUGH SCHDUF, FOR CAND=CAND+1, 1, DUFF.(CAND)

DUFCOL OUTROW(C) = CAND

DUFROW PRINT FORMAT ROWFMT,OUTROW(0),OUTROW(1),OUTROW(2),

0 OUTROW(3),OUTROW(4),OUTROW(5),OUTROW(6),

1 OUTROW(7),OUTROW(8),OUTROW(9)

PRINT COMMENT $ $

PRINT COMMENT $ FIRST 15 DUFFINIAN TRIPLETS$

CAND = 0

THROUGH DUFTRI, FOR S=0, 1, S.GE.15

SCHTRP THROUGH SCHTRP, FOR CAND=CAND+1, 1, TRIP.(CAND)

DUFTRI PRINT FORMAT TRIFMT,CAND,CAND+1,CAND+2

VECTOR VALUES ROWFMT = $10(I5)*$

VECTOR VALUES TRIFMT = $3(I7)*$

END OF PROGRAM</syntaxhighlight>

{{out}}

<pre>FIRST 50 DUFFINIAN NUMBERS

4 8 9 16 21 25 27 32 35 36

39 49 50 55 57 63 64 65 75 77

81 85 93 98 100 111 115 119 121 125

128 129 133 143 144 155 161 169 171 175

183 185 187 189 201 203 205 209 215 217

FIRST 15 DUFFINIAN TRIPLETS

63 64 65

323 324 325

511 512 513

721 722 723

899 900 901

1443 1444 1445

2303 2304 2305

2449 2450 2451

3599 3600 3601

3871 3872 3873

5183 5184 5185

5617 5618 5619

6049 6050 6051

6399 6400 6401

8449 8450 8451</pre>