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A064649 Row sums of the table A047916. 4
1, 4, 12, 40, 140, 816, 5082, 40800, 363258, 3632880, 39916910, 479052528, 6227020956, 87178936992, 1307674429440, 20922800222848, 355687428096272, 6402373892575992, 121645100408832342, 2432902011892837920 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

LINKS

Harry J. Smith, Table of n, a(n) for n=1,...,100

MAPLE

A064649 := proc(n) local d, s; s := 0; for d in divisors(n) do s := s + phi(n/d)*(n/d)^d*d!; od; RETURN(s); end;

PROG

(PARI) { for (n=1, 100, a=0; v=divisors(n); for (i=1, length(v), d=v[i]; a+=eulerphi(n/d)*(n/d)^d*d!); write("b064649.txt", n, " ", a) ) } [From Harry J. Smith (hjsmithh(AT)sbcglobal.net), Sep 21 2009]

CROSSREFS

Also n*A061417[n]. Cf. A047918, A002619.

Sequence in context: A081875 A102433 A100320 * A149332 A149333 A074450

Adjacent sequences:  A064646 A064647 A064648 * A064650 A064651 A064652

KEYWORD

nonn

AUTHOR

Antti Karttunen Oct 04 2001

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Last modified February 17 21:13 EST 2012. Contains 206085 sequences.