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A125704 Table read by antidiagonals: row n contains the positive integers (in order) which are coprime to the n-th prime. 2
1, 1, 3, 1, 2, 5, 1, 2, 4, 7, 1, 2, 3, 5, 9, 1, 2, 3, 4, 7, 11, 1, 2, 3, 4, 6, 8, 13, 1, 2, 3, 4, 5, 7, 10, 15, 1, 2, 3, 4, 5, 6, 8, 11, 17, 1, 2, 3, 4, 5, 6, 8, 9, 13, 19, 1, 2, 3, 4, 5, 6, 7, 9, 11, 14, 21, 1, 2, 3, 4, 5, 6, 7, 8, 10, 12, 16, 23, 1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 13, 17, 25, 1, 2, 3, 4, 5 (list; table; graph; refs; listen; history; internal format)
OFFSET

1,3

FORMULA

T(1,m)=A005408(m). T(2,m)=A001651(m). T(3,m)=A047201(m). T(4,m)=A047304(m). - R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Feb 02 2007

T(n,m)=m-1+floor((m+p(n)-2)/(p(n)-1)) where p(n)=n-th prime [From Benoit Cloitre (benoit7848c(AT)orange.fr), Jul 11 2009]

EXAMPLE

Beginning of table:

1,3,5,7,9,11,13,...

1,2,4,5,7,8,10,11,...

1,2,3,4,6,7,8,9,11,...

1,2,3,4,5,6,8,9,10,...

MAPLE

A125704 := proc(n, m) local p, i, a ; p := ithprime(n) ; a := 1 ; for i from 2 to m do a := a+1 ; while gcd(a, p) <> 1 do a := a+1 ; od ; od ; RETURN(a) ; end : maxdiag := 15 ; for d from 1 to maxdiag do for n from d to 1 by -1 do printf("%d, ", A125704(n, d-n+1)) ; od ; od; - R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Feb 02 2007

PROG

(PARI) T(n, m)=m-1+floor((m+prime(n)-2)/(prime(n)-1)) [From Benoit Cloitre (benoit7848c(AT)orange.fr), Jul 11 2009]

CROSSREFS

Sequence in context: A123375 A021036 A080521 * A131127 A113141 A134225

Adjacent sequences:  A125701 A125702 A125703 * A125705 A125706 A125707

KEYWORD

nonn,tabl

AUTHOR

Leroy Quet Jan 31 2007

EXTENSIONS

More terms from R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Feb 02 2007

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Last modified February 16 16:51 EST 2012. Contains 205938 sequences.