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 A127641 A127640 * A051731 as infinite lower triangular matrices. 3
 2, 3, 3, 5, 0, 5, 7, 7, 0, 7, 11, 0, 0, 0, 11, 13, 13, 13, 0, 0, 13, 17, 0, 0, 0, 0, 0, 17, 19, 19, 0, 19, 0, 0, 0, 19, 23, 0, 23, 0, 0, 0, 0, 0, 23, 29, 29, 0, 0, 29, 0, 0, 0, 0, 29, 31, 0, 0, 0, 0, 0, 0, 0, 0, 0, 31, 37, 37, 37, 37, 0, 37, 0, 0, 0, 0, 0, 37, 41, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 41 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS A prime transform of A051731. LINKS EXAMPLE First few rows of the triangle are: 2; 3, 3; 5, 0, 5; 7, 7, 0, 7; 11, 0, 0, 0, 11; 13, 13, 13, 0, 0, 13; ... MAPLE A127640 := proc(n, m) if m < n then 0; else ithprime(n) ; fi ; end: A051731 := proc(n, k) if n mod k = 0 then 1 ; else 0 ; fi ; end: A127641 := proc(n, m) add( A127640(n, k)*A051731(k, m), k=1..n) ; end: for n from 1 to 15 do for m from 1 to n do printf("%d, ", A127641(n, m)) ; od ; od ; # R. J. Mathar, May 19 2007 CROSSREFS Cf. A127640, A051731, A127638, A127639. Sequence in context: A290818 A240376 A118963 * A106821 A065863 A049272 Adjacent sequences:  A127638 A127639 A127640 * A127642 A127643 A127644 KEYWORD nonn,tabl,easy AUTHOR Gary W. Adamson, Jan 21 2007 EXTENSIONS More terms from R. J. Mathar, May 19 2007 STATUS approved

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Last modified October 13 23:47 EDT 2019. Contains 327983 sequences. (Running on oeis4.)