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A134713 Base-2 logarithm of (n-th even superperfect number divided by 2^n), plus 1. 0
1, 1, 2, 3, 8, 11, 12, 23, 52, 79, 96, 115, 508, 593, 1264, 2187, 2264, 3199, 4234, 4403, 9668, 9919, 11190, 19913, 21676, 23183, 44470, 86215, 110474, 132019, 216060, 756807, 859400, 1257753, 1398234, 2976185, 3021340, 6972555, 13466878 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Table of n, a(n) for n=1..39.

Omar E. Pol, Determinacion geometrica de los numeros primos y perfectos.

FORMULA

a(n) = 1 + log_2(A061652(n)/(2^n)) = A000043(n) - n = A090748(n) - n + 1.

EXAMPLE

a(5)=8 because the 5th even superperfect number is 4096, 2^5 = 32, 4096/32=128, log_2(128) = 7 (because 2^7=128) and 7+1 = 8.

CROSSREFS

Cf. A000043, A000396, A000668, A019279, A061652, A090748, A133028.

Sequence in context: A118089 A201541 A084917 * A293910 A173269 A050557

Adjacent sequences:  A134710 A134711 A134712 * A134714 A134715 A134716

KEYWORD

nonn

AUTHOR

Omar E. Pol, Nov 07 2007

STATUS

approved

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Last modified October 26 06:55 EDT 2021. Contains 348257 sequences. (Running on oeis4.)