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A101805 Number of Ruth-Aaron numbers (with multiplicity) less than 10^n. 1
2, 4, 7, 20, 57, 149, 523, 1835, 6810, 26222, 106670, 444085 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..12.

Eric Weisstein's World of Mathematics, Ruth-Aaron Pair

CROSSREFS

Cf. A039752.

Sequence in context: A225435 A243049 A247234 * A145777 A188497 A237759

Adjacent sequences:  A101802 A101803 A101804 * A101806 A101807 A101808

KEYWORD

nonn,more

AUTHOR

Eric W. Weisstein, Dec 16 2004

EXTENSIONS

Offset corrected and a(9)-a(12) from Donovan Johnson, Dec 14 2010

STATUS

approved

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Last modified June 28 13:23 EDT 2017. Contains 288828 sequences.