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A003962 Completely multiplicative with a(p(k)) = floor( (p(k+1)+1)/2 ) for k-th prime p(k). 2
1, 2, 3, 4, 4, 6, 6, 8, 9, 8, 7, 12, 9, 12, 12, 16, 10, 18, 12, 16, 18, 14, 15, 24, 16, 18, 27, 24, 16, 24, 19, 32, 21, 20, 24, 36, 21, 24, 27, 32, 22, 36, 24, 28, 36, 30, 27, 48, 36, 32, 30, 36, 30, 54, 28, 48, 36, 32, 31, 48, 34, 38, 54, 64, 36, 42, 36, 40, 45, 48, 37, 72, 40, 42, 48, 48 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..76.

Index to divisibility sequences

FORMULA

Multiplicative with a(p^e) = ((A000040(A000720(p)+1)+1)/2)^e. - David W. Wilson, Aug 01 2001

PROG

(PARI) tcp(n) = my(f=factor(n)); for (i=1, #f~, f[i, 1] = (nextprime(f[i, 1]+1)+1)/2); factorback(f); \\ Michel Marcus, Jun 09 2014

CROSSREFS

Sequence in context: A138768 A111939 A253248 * A102443 A102441 A102440

Adjacent sequences:  A003959 A003960 A003961 * A003963 A003964 A003965

KEYWORD

nonn,mult

AUTHOR

Marc LeBrun

EXTENSIONS

Corrected and extended by David W. Wilson.

STATUS

approved

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Last modified June 25 22:21 EDT 2019. Contains 324358 sequences. (Running on oeis4.)