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A186943 Number of lunar divisors (in base 10) of the n-th number whose decimal expansion contains only 0's and 1's and begins and ends with a 1 (A099821(n)). 2
9, 90, 90, 819, 90, 738, 738, 7461, 90, 738, 819, 6570, 738, 6732, 6570, 67968, 90, 738, 738, 6570, 738, 6570, 6732, 59868, 738, 6732, 6570, 59868, 6570, 59868, 59868, 619902, 90, 738, 738, 6570, 819, 6570, 6570, 59058, 738, 6570, 7461, 59058, 6570, 59868, 59058, 539550, 738, 6732, 6570, 59868, 6570, 59058, 59868, 538821, 6570, 59868, 59058, 538902, 59058, 538821, 539550, 5660208, 90, 738, 738, 6570, 738, 6570, 6570 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Number of lunar divisors of A099821(n), that is, A087029(A099821(n))..

LINKS

N. J. A. Sloane, Table of n, a(n) for n = 1..100

D. Applegate, M. LeBrun and N. J. A. Sloane, Dismal Arithmetic [Note: we have now changed the name from "dismal arithmetic" to "lunar arithmetic" - the old name was too depressing]

Index entries for sequences related to dismal (or lunar) arithmetic

EXAMPLE

1 has 9 divisors: 1,2,3,4,5,6,7,8,9, so a(1)=9. 11 has 90 divisors, 1 through 9 and the numbers 11 through 99 that do not end in 0, so a(2)=90.

CROSSREFS

Cf. A087029, A099821.

Sequence in context: A230114 A187090 A078248 * A217402 A261908 A121029

Adjacent sequences:  A186940 A186941 A186942 * A186944 A186945 A186946

KEYWORD

nonn,base

AUTHOR

N. J. A. Sloane, Mar 01 2011

STATUS

approved

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Last modified September 17 16:32 EDT 2021. Contains 347487 sequences. (Running on oeis4.)