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A081401 Pseuodologarithm (A056239) of n!: a(n)=A056239[A000142(n)]. 0
1, 3, 5, 8, 11, 15, 18, 22, 26, 31, 35, 41, 46, 51, 55, 62, 67, 75, 80, 86, 92, 101, 106, 112, 119, 125, 131, 141, 147, 158, 163, 170, 178, 185, 191, 203, 212, 220, 226, 239, 246, 260, 267, 274, 284, 299, 305, 313, 320, 329, 337, 353, 360, 368, 375, 385, 396, 413 (list; graph; refs; listen; history; internal format)
OFFSET

2,2

FORMULA

a(n)=Sum[k*e(k)] where k runs through indices of prime factors of n!, while e(k) is the exponent of corresponding prime factor.

EXAMPLE

n=8: 8!=40320=2.2.2.2.2.2.2.3.3.5.7, p-indices={1,2,3,4}, exponents={7,2,1,1}; a(8)=1.7+2.2+3.1+4.1=7+4+3+4=18.

CROSSREFS

Cf. A056239, A000142.

Sequence in context: A062009 A062484 A022433 * A003311 A108279 A002821

Adjacent sequences:  A081398 A081399 A081400 * A081402 A081403 A081404

KEYWORD

nonn

AUTHOR

Labos E. (labos(AT)ana.sote.hu), Mar 31 2003

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Last modified February 17 00:09 EST 2012. Contains 205978 sequences.