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A259849 Average of consecutive pairs of perfect numbers. 1
17, 262, 4312, 16779232, 4311709696, 73014280192, 1152921572789321728, 1329227995784915873480267812046897152, 95780971304118054976624684827067691392844968751005696 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Assuming that no odd perfect number exists.

LINKS

Table of n, a(n) for n=1..9.

FORMULA

a(n) = (A000396(n)+A000396(n+1))/2, assuming there are no odd perfect numbers.

EXAMPLE

a(1) = (6 + 28)/2 = 17.

MAPLE

perf:= n -> numtheory:-mersenne([n])*(numtheory:-mersenne([n])+1)/2:

seq((perf(n)+perf(n+1))/2, n=1..15); # Robert Israel, Aug 20 2015

CROSSREFS

Cf. A000396.

Sequence in context: A001282 A135214 A218120 * A090380 A142898 A159678

Adjacent sequences:  A259846 A259847 A259848 * A259850 A259851 A259852

KEYWORD

nonn

AUTHOR

José de Jesús Camacho Medina, Aug 17 2015

STATUS

approved

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Last modified July 23 03:00 EDT 2019. Contains 325230 sequences. (Running on oeis4.)