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A085890 Highly composite numbers (A002473) using digits in descending order. 1 is followed by a zero. 1
1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 21, 32, 54, 98, 210, 432 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

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

LINKS

Table of n, a(n) for n=1..16.

EXAMPLE

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

PROG

(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 */

CROSSREFS

Cf. A002473, A085889.

Sequence in context: A247107 A061511 A138142 * A274842 A134817 A067581

Adjacent sequences:  A085887 A085888 A085889 * A085891 A085892 A085893

KEYWORD

base,nonn

AUTHOR

Amarnath Murthy and Meenakshi Srikanth (menakan_s(AT)yahoo.com), Jul 10 2003

EXTENSIONS

More terms from David Wasserman, Feb 10 2005

STATUS

approved

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Last modified March 2 12:26 EST 2021. Contains 341750 sequences. (Running on oeis4.)