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A138873
First two digits of n-th even perfect number.
2
6, 28, 49, 81, 33, 85, 13, 23, 26, 19, 13, 14, 23, 14, 54, 10, 99, 33, 18, 40, 11, 59, 39, 93, 10, 81, 36, 14, 13, 13, 27, 15, 83, 84, 33, 19, 81, 95, 42, 79, 44, 74, 49, 77, 20, 14, 50
OFFSET
1,1
LINKS
Jan Munch Pedersen, Known Perfect Numbers [Steven Bi (chenhsi(AT)stanford.edu), Jan 18 2009]
MATHEMATICA
Join[{6}, FromDigits[Take[IntegerDigits[#], 2]]&/@PerfectNumber[Range[2, 50]]] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Sep 26 2020 *)
CROSSREFS
First 2 digits of sequence A138875. [Steven Bi (chenhsi(AT)stanford.edu), Jan 18 2009]
Sequence in context: A055196 A323752 A120624 * A377095 A091307 A254879
KEYWORD
base,more,nonn
AUTHOR
Omar E. Pol, Apr 02 2008
EXTENSIONS
a(15)-a(31) added by Steven Bi (chenhsi(AT)stanford.edu), Jan 18 2009
Definition changed (inserting the word "even") and a(37)-a(47) added by Ivan Panchenko, Aug 04 2018
STATUS
approved