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A075633
Initial terms of groups in A075631.
4
1, 2, 3, 6, 19, 99, 307, 9379, 1726174, 13347339102, 321699559882750174, 4716070968330003553938242926174, 23987291841663781653328392594255840802707701158676395299
OFFSET
1,2
FORMULA
For n>1, a(n) = A075634(n-1) + 1. Also, a(n) = (sqrt(8*(A075631(1) + A075631(2) + ... + A075631(n-1)) + 1) + 1) / 2. [From Max Alekseyev, May 08 2009]
CROSSREFS
KEYWORD
nonn
AUTHOR
Amarnath Murthy, Sep 30 2002
EXTENSIONS
More terms from Jonathan Cross (jcross(AT)juggler.net), May 08 2004
One more term from Max Alekseyev, May 08 2009
STATUS
approved