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A140706 A054525 * A014683. 1
1, 2, 3, 1, 5, 0, 7, 4, 5, 2, 11, 5, 13, 4, 6, 8, 17, 7, 19, 9, 10, 8, 23, 8, 19, 10, 18, 13, 29, 11, 31, 16, 18, 14, 22, 12, 37, 16, 22, 16, 41, 15, 43, 21, 25, 20, 47, 16, 41, 21, 30, 25, 53, 18, 38, 24, 34, 26, 59, 15, 61, 28, 37, 32, 46, 23, 67, 33, 42, 27, 71, 24, 73, 34, 41 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

a(n) = n iff n is prime.

LINKS

Table of n, a(n) for n=1..75.

FORMULA

Mobius transform of A014683: (1, 3, 4, 4, 6, 6, 8, 8, 9, 10,...); where A014683(n) = n if n is not prime; but (n+1) if n is prime.

EXAMPLE

a(4) = 1 = (0, -1, 0, 1) dot (1, 3, 4, 4), where (0, -1, 0, 1) = row 4 of triangle A054525.

MAPLE

read("transforms") : A014683 := proc(n) if isprime(n) then 1+n; else n; fi; end: a014683 := [seq(A014683(n), n=1..150)] ; a140706 := MOBIUS(a014683) ; for i from 1 to nops(a140706) do printf("%d, ", op(i, a140706)) ; od: [From R. J. Mathar, Jan 19 2009]

CROSSREFS

Cf. A014683, A054525.

Sequence in context: A201737 A080063 A187680 * A200068 A139764 A227643

Adjacent sequences:  A140703 A140704 A140705 * A140707 A140708 A140709

KEYWORD

nonn

AUTHOR

Gary W. Adamson, May 24 2008

EXTENSIONS

More terms from R. J. Mathar, Jan 19 2009

STATUS

approved

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Last modified September 17 23:53 EDT 2014. Contains 246886 sequences.