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A085890 Highly composite numbers (A002473) using digits in descending order. 1 is followed by a zero. 1

%I

%S 1,2,3,4,5,6,7,8,9,10,21,32,54,98,210,432

%N Highly composite numbers (A002473) using digits in descending order. 1 is followed by a zero.

%C No more terms < 10^1000. Probably no more terms. - David Wasserman, Feb 10 2005

%e 432 is a member as 432= 2^4*3^3.

%o (PARI) hcn(n) = while (!(n%2), n \=2); while (!(n%3), n \=3); while (!(n%5), n \=5); while (!(n%7), n \=7); n == 1; for (i = 0, 1000, for (j = 1, 9, n = sum(k = j - i, j, (k%10)*10^(i - j + k)); if (hcn(n), print(n)))); /* David Wasserman */

%Y Cf. A002473, A085889.

%K base,nonn

%O 1,2

%A _Amarnath Murthy_ and Meenakshi Srikanth (menakan_s(AT)yahoo.com), Jul 10 2003

%E More terms from _David Wasserman_, Feb 10 2005

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Last modified April 18 05:44 EDT 2021. Contains 343072 sequences. (Running on oeis4.)