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A053239 First differences between n for which sigma(n) > sigma(n+1), which are not 2. 7
4, 1, 1, 4, 4, 1, 1, 1, 1, 4, 4, 1, 1, 4, 4, 1, 1, 4, 1, 1, 1, 1, 3, 1, 1, 1, 1, 1, 4, 3, 1, 4, 1, 1, 4, 4, 1, 1, 3, 1, 4, 1, 1, 4, 1, 1, 4, 1, 1, 4, 4, 4, 3, 1, 1, 1, 4, 4, 3, 1, 1, 1, 4, 4, 1, 1, 1, 1, 4, 1, 1, 1, 1, 4, 3, 1, 4, 4, 1, 1, 4, 4, 1, 1, 3, 1, 3, 1, 1, 1, 1, 1, 4, 4, 1, 1, 4, 1, 1, 4, 4, 3, 1, 3, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..105.

FORMULA

The expansion of A053238 excluding 2's. a(n) = A053238(A053240(n)).

MAPLE

with(numtheory): f := [seq( `if`((sigma(i) > sigma(i+1)), i, print( )), i=1..5000)];

seq( `if`(f[i+1] - f[i] <> 2, f[i+1] - f[i], print( )), i=1..2000);

CROSSREFS

Cf. A000203, A053226, A053238, A053240, A053241, A053242, A053243, A053244, A053245.

Sequence in context: A131776 A010322 A299537 * A046569 A046596 A174093

Adjacent sequences:  A053236 A053237 A053238 * A053240 A053241 A053242

KEYWORD

nonn

AUTHOR

Asher Auel (asher.auel(AT)reed.edu), Jan 10 2000

STATUS

approved

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Last modified July 15 02:31 EDT 2020. Contains 335762 sequences. (Running on oeis4.)