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A074375 s(s+3)/2 where s is the sum of the prime factors of n (with repetition). 2
0, 5, 9, 14, 20, 20, 35, 27, 27, 35, 77, 35, 104, 54, 44, 44, 170, 44, 209, 54, 65, 104, 299, 54, 65, 135, 54, 77, 464, 65, 527, 65, 119, 209, 90, 65, 740, 252, 152, 77, 902, 90, 989, 135, 77, 350, 1175, 77, 119, 90, 230, 170, 1484, 77, 152, 104, 275, 527, 1829, 90 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..60.

Neville Holmes, Integer Sequence Combinations

EXAMPLE

a(20) = 9(9+3)/2 = 54 because 9 = 2+2+5 and 20 = 2*2*5.

MATHEMATICA

spf[n_]:=Module[{c=Total[Times@@@FactorInteger[n]]}, (c(c+3))/2]; Join[ {0}, Rest[Array[spf, 60]]] (* Harvey P. Dale, Aug 16 2011 *)

CROSSREFS

Applies A000096 to A001414. Cf. A074373, A074374.

Sequence in context: A314925 A314926 A314927 * A314928 A314929 A314930

Adjacent sequences:  A074372 A074373 A074374 * A074376 A074377 A074378

KEYWORD

easy,nonn

AUTHOR

W. Neville Holmes, Aug 29 2002

STATUS

approved

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Last modified October 22 22:34 EDT 2019. Contains 328335 sequences. (Running on oeis4.)