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A130419
Triangle (of n terms per row) where t(n,m) = the m-th positive integer which is coprime to n!!. (n!! = n*(n-2)*(n-4)..*(2 or 1).).
3
1, 1, 3, 1, 2, 4, 1, 3, 5, 7, 1, 2, 4, 7, 8, 1, 5, 7, 11, 13, 17, 1, 2, 4, 8, 11, 13, 16, 1, 5, 7, 11, 13, 17, 19, 23, 1, 2, 4, 8, 11, 13, 16, 17, 19, 1, 7, 11, 13, 17, 19, 23, 29, 31, 37, 1, 2, 4, 8, 13, 16, 17, 19, 23, 26, 29, 1, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 1, 2, 4, 8, 16, 17
OFFSET
1,3
MAPLE
A130419 := proc(n, m) local ndf, mprime, a ; ndf := doublefactorial(n) ; a := 0 ; for mprime from 1 to m do a := a+1 ; while gcd(a, ndf) <> 1 do a := a+1 ; od ; od ; RETURN(a) ; end: for n from 1 to 15 do for m from 1 to n do printf("%d, ", A130419(n, m)) ; od ; od ; # R. J. Mathar, Jun 06 2007
MATHEMATICA
T[n_, m_] := Module[{ndf = n!!, mprime, a = 0}, For[mprime = 1, mprime <= m, mprime++, a++; While[GCD[a, ndf] != 1, a++]]; Return[a]];
Table[T[n, m], {n, 1, 15}, {m, 1, n}] // Flatten (* Jean-François Alcover, Jul 21 2024, after R. J. Mathar *)
CROSSREFS
Sequence in context: A016468 A134839 A077581 * A083110 A059016 A080418
KEYWORD
nonn,tabl
AUTHOR
Leroy Quet, May 25 2007
EXTENSIONS
More terms from R. J. Mathar, Jun 06 2007
STATUS
approved