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A057531 Numbers n such that sum of digits of n equals the numbers of divisors of n. 17
1, 2, 11, 22, 36, 84, 101, 152, 156, 170, 202, 208, 225, 228, 288, 301, 372, 396, 441, 444, 468, 516, 525, 530, 602, 684, 710, 732, 804, 828, 882, 952, 972, 1003, 1016, 1034, 1070, 1072, 1106, 1111, 1164, 1236, 1304, 1308, 1425, 1472, 1476, 1521, 1524 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

[A007953(n)/A000005(n) = c] AND [A000005(n)/A007953(n) = c], c an integer. [Ctibor O. Zizka, Jun 26 2009]

LINKS

Giovanni Resta, Table of n, a(n) for n = 1..10000 (first 210 terms from Daniel Arribas)

EXAMPLE

36 is a member as the sum of the digits of 36 is 3+6 = 9 and the number of divisors is 9 too.

MATHEMATICA

Select[ Range[ 1000 ], DivisorSigma[ 0, # ]==Plus@@IntegerDigits[ # ]& ] (* _Harvey Dale_, Feb 19 2004 *)

CROSSREFS

Cf. A000005, A007953, A057532, A050689, A070274, A070275, A063737, A067077.

Sequence in context: A076206 A018563 A018590 * A018661 A259298 A018711

Adjacent sequences:  A057528 A057529 A057530 * A057532 A057533 A057534

KEYWORD

nonn,easy,base

AUTHOR

Asher Auel (asher.auel(AT)reed.edu), Sep 03 2000

STATUS

approved

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Last modified July 21 02:59 EDT 2017. Contains 289629 sequences.