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A294952 Triangle read by rows: T(n,k) is the number of n-digit numbers having a k-digit greatest prime factor. 1
9, 36, 54, 95, 470, 335, 197, 2854, 3547, 2402, 356, 13370, 31999, 25577, 18698, 579, 54250, 236147, 256465, 199403, 153156, 882, 196729, 1486448, 2386859, 1999848, 1633601, 1295633, 1272, 653419, 8615121, 19298617, 19999102, 16384481, 13828384, 11219604 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

By convention, gpf(1) = 1; see A006530.

LINKS

Charles R Greathouse IV, Table of n, a(n) for n = 1..66

EXAMPLE

Table begins

     9;

    36,     54;

    95,    470,     335;

   197,   2854,    3547,     2402;

   356,  13370,   31999,    25577,    18698;

   579,  54250,  236147,   256465,   199403,  153156;

   882, 196729, 1486448,  2386859,  1999848,  1633601,  1295633;

  1272, 653419, 8615121, 19298617, 19999102, 16384481, 13828384, 11219604;

PROG

(PARI) row(n)=if(n<2, return([9])); my(v=vector(n)); forfactored(k=10^(n-1), 10^n-1, v[#Str(vecmax(k[2][, 1]))]++); v \\ Charles R Greathouse IV, Nov 12 2017

CROSSREFS

Cf. A006530.

First column gives A085630.

Sequence in context: A329808 A169580 A258844 * A068810 A077115 A297584

Adjacent sequences:  A294949 A294950 A294951 * A294953 A294954 A294955

KEYWORD

nonn,base,tabl

AUTHOR

Jon E. Schoenfield, Nov 11 2017

STATUS

approved

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Last modified December 14 09:41 EST 2019. Contains 329979 sequences. (Running on oeis4.)