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 A100757 Smallest prime factor of the concatenation of terms of the n-th row of the Stirling's number of the second kind. 1
 11, 131, 3, 7, 101, 9066319, 3, 3, 89, 3, 1721, 13, 8761, 1213, 7, 3, 1056688498936034269, 37, 29, 3, 3, 11, 3, 19457, 7, 19, 11, 307, 3, 521, 7, 11887, 3, 3, 7, 3, 13, 11, 103, 43, 22927346902711843, 3, 17, 13, 31, 3, 3, 7, 3, 133811, 37, 11, 13 (list; graph; refs; listen; history; text; internal format)
 OFFSET 2,1 COMMENTS Sequences from other important triangles with unity as the first and the last term can be contributed. A061113(8) is the first member of A061113 that is not squarefree; it is divisible by 3^3. - David Wasserman, Mar 06 2008 LINKS FORMULA a(n) = A020639[A061113(n)]. - R. J. Mathar, Aug 07 2007 EXAMPLE a(4) = 3 is the least prime factor of 1761. CROSSREFS Cf. A100755, A100756, A100758, A008277. Sequence in context: A157718 A256957 A046210 * A099677 A142187 A201484 Adjacent sequences:  A100754 A100755 A100756 * A100758 A100759 A100760 KEYWORD base,easy,nonn AUTHOR Amarnath Murthy, Nov 23 2004 EXTENSIONS More terms from R. J. Mathar, Aug 07 2007 More terms from David Wasserman, Mar 06 2008 STATUS approved

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Last modified August 10 16:24 EDT 2022. Contains 356039 sequences. (Running on oeis4.)