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A075493 Numbers k such that (sum of digits of k) > (number of divisors of k). 3
3, 4, 5, 6, 7, 8, 9, 13, 14, 15, 16, 17, 18, 19, 23, 25, 26, 27, 28, 29, 31, 33, 34, 35, 37, 38, 39, 41, 43, 44, 45, 46, 47, 48, 49, 51, 52, 53, 54, 55, 56, 57, 58, 59, 61, 62, 63, 64, 65, 66, 67, 68, 69, 71, 73, 74, 75, 76, 77, 78, 79, 81, 82, 83, 85, 86, 87, 88, 89, 91, 92 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..71.

FORMULA

Solutions to A007953(k) > A000005(k).

EXAMPLE

Sequence includes all primes with sum of digits > 2, i.e., all primes not of the form 10^d + 1 for nonnegative integers d (the only known primes of this form are 2, 11, and 101; see A185121).

Sequence also includes all squared primes with sum of digits > 3.

MATHEMATICA

sud[x_] := Apply[Plus, IntegerDigits[x]] Do[s=sud[n]-DivisorSigma[0, n]; If[s>0, Print[n]], {n, 1, 256}]

Select[Range[100], Total[IntegerDigits[#]]>DivisorSigma[0, #]&] (* Harvey P. Dale, Mar 07 2020 *)

CROSSREFS

Cf. A007953, A000005, A057531, A075492, A075491, A185121.

Sequence in context: A096829 A265126 A039120 * A096828 A097389 A051415

Adjacent sequences:  A075490 A075491 A075492 * A075494 A075495 A075496

KEYWORD

base,easy,nonn

AUTHOR

Labos Elemer, Sep 26 2002

EXTENSIONS

Edited by Jon E. Schoenfield, Sep 23 2018

STATUS

approved

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Last modified August 12 23:52 EDT 2022. Contains 356077 sequences. (Running on oeis4.)