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A134713
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Base-2 logarithm of (n-th even superperfect number divided by 2^n), plus 1.
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0
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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
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OFFSET
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1,3
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LINKS
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Table of n, a(n) for n=1..39.
Omar E. Pol, Determinacion geometrica de los numeros primos y perfectos.
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FORMULA
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a(n) = 1 + log_2(A061652(n)/(2^n)) = A000043(n) - n = A090748(n) - n + 1.
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EXAMPLE
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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.
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CROSSREFS
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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
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KEYWORD
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nonn
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AUTHOR
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Omar E. Pol, Nov 07 2007
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STATUS
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approved
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