A097421 - OEIS

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A097421

a(n) = (5^(2^n) - 1)/2^(n+2).

5

1, 3, 39, 12207, 2384185791, 181898940354585647583, 2117582368135750847670806251699104905128479, 573971850987445072250359637315549647372395291392620860111695169081258427468128502368927

(list; graph; refs; listen; history; text; internal format)

OFFSET

0,2

LINKS

Table of n, a(n) for n=0..7.

MATHEMATICA

Table[(5^(2^n)-1)/2^(n+2), {n, 0, 10}] (* Harvey P. Dale, Aug 07 2025 *)

CROSSREFS

Sequence in context: A076628 A198411 A367033 * A180418 A166999 A319955

Adjacent sequences: A097418 A097419 A097420 * A097422 A097423 A097424

KEYWORD

nonn

AUTHOR

Lekraj Beedassy, Aug 21 2004

STATUS

approved