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1,2
T. D. Noe, Table of n, a(n) for n = 1..10000
(PARI) a(n)=sigma(n+2)-2*sigma(n+1)+sigma(n) \\ Charles R Greathouse IV, Mar 09 2014
Cf. A000203, A053222, A053228, A053229, A053247, A053248.
Sequence in context: A059186 A034702 A167206 * A153383 A177093 A164903
Adjacent sequences: A053220 A053221 A053222 * A053224 A053225 A053226
sign
Asher Auel (asher.auel(AT)reed.edu) Jan 06 2000
approved