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A145198
a(n) is the least number not already in the sequence and not the product of consecutive terms in the sequence.
2
1, 2, 3, 4, 5, 7, 8, 9, 10, 11, 13, 14, 15, 16, 17, 18, 19, 21, 22, 23, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 57, 58, 59, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 73, 74, 75, 76, 77, 78, 79, 80
OFFSET
1,2
LINKS
PROG
(PARI) {m=72; v=vector(m); z=2*m; u=vectorsmall(z); k=1; for(n=1, m, while(u[k], k++); v[n]=k; u[k]=1; j=n-1; p=k; while(j>0&&(p=p*v[j])<=z, u[p]=1; j--)); for(i=1, m, print1(v[i], ", "))} \\ Klaus Brockhaus, Oct 06 2008
(Other)
HP 49G calculator program from Gerald Hillier, Oct 24 2008
<< 0 OVER NDUPN
->LIST DUPDUP + 1 0
0 -> M V U K J P
<< 1 M
FOR N K
WHILE U OVER
GET
REPEAT 1 +
END 'K' STO V
N K PUT 'V' STO U K
1 PUT N 1 - 'J' STO
K 'P' STO
WHILE J 0 >
IF
THEN P V J
GET * DUP 'P' STO M
2 * <=
ELSE 0
END
REPEAT P 1
PUT J 1 - 'J' STO
END 'U' STO
NEXT V
>>
>>
CROSSREFS
Cf. A002048, A145278 (complement).
Sequence in context: A121229 A286291 A286926 * A083210 A345913 A187392
KEYWORD
nonn
AUTHOR
Gerald Hillier, Oct 04 2008
EXTENSIONS
Extended by Klaus Brockhaus, Oct 06 2008
STATUS
approved