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A059292 a(n) = n + 2 - (number of divisors of n). 2
2, 2, 3, 3, 5, 4, 7, 6, 8, 8, 11, 8, 13, 12, 13, 13, 17, 14, 19, 16, 19, 20, 23, 18, 24, 24, 25, 24, 29, 24, 31, 28, 31, 32, 33, 29, 37, 36, 37, 34, 41, 36, 43, 40, 41, 44, 47, 40, 48, 46, 49, 48, 53, 48, 53, 50, 55, 56, 59, 50, 61, 60, 59, 59, 63, 60, 67 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

REFERENCES

L. Comtet, Advanced Combinatorics, Reidel, 1974, p. 121, see #17.

LINKS

Harry J. Smith, Table of n, a(n) for n = 1..5000

FORMULA

a(n) = n + 2 - A000005(n) = A049820(n) + 2. - Omar E. Pol, Jul 16 2009

MATHEMATICA

Table[n + 2 - DivisorSigma[0, n], {n, 1, 100}] (* G. C. Greubel, Jan 04 2017 *)

(MAGMA) [n+2-DivisorSigma(0, n): n in [1..100]]; // Vincenzo Librandi, Jan 05 2017

PROG

(PARI) { for (n = 1, 5000, write("b059292.txt", n, " ", n + 2 - numdiv(n)); ) } \\ Harry J. Smith, Jun 25 2009

CROSSREFS

Cf. A000005, A049820, A062968. - Omar E. Pol, Jul 16 2009

Sequence in context: A114092 A082500 A194451 * A115000 A036825 A035574

Adjacent sequences:  A059289 A059290 A059291 * A059293 A059294 A059295

KEYWORD

nonn

AUTHOR

N. J. A. Sloane, Jan 25 2001

STATUS

approved

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Last modified November 15 11:35 EST 2018. Contains 317238 sequences. (Running on oeis4.)