OFFSET
1,2
COMMENTS
a(n+1)/a(n) >= 2 for all n. Is a(n+1)/a(n) bounded? Up to n=160, the maximum value is a(31)/a(30)=2.5125261124174184479... - Benoit Cloitre, Apr 17 2003
a(n) == 23 (mod 24) for all n>=5. - Dean Hickerson, Apr 20 2003
a(n) = partial sums of A165929(n). [From Jaroslav Krizek, Sep 30 2009]
LINKS
T. D. Noe, Table of n, a(n) for n=1..200
MATHEMATICA
a[1]=1; a[n_] := a[n]=a[n-1]+DivisorSigma[1, a[n-1]]
CROSSREFS
KEYWORD
nonn
AUTHOR
Amarnath Murthy, Apr 03 2003
EXTENSIONS
More terms from Gabriel Cunningham (gcasey(AT)mit.edu), Apr 07 2003
STATUS
approved