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A048521 Primes expressible as the sum of an integer plus its digit sum. 7
2, 11, 13, 17, 19, 23, 29, 37, 41, 43, 47, 59, 61, 67, 71, 73, 79, 83, 89, 101, 103, 107, 109, 113, 127, 131, 137, 139, 149, 151, 157, 163, 167, 173, 179, 181, 191, 193, 197, 199, 223, 227, 229, 239, 241, 251, 257, 263, 269, 271, 281, 283, 293, 307, 311, 313 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

Index entries for Colombian or self numbers and related sequences

FORMULA

A107740(A049084(a(n))) > 0.

EXAMPLE

E.g. a(24) = prime 113 which is 106 + (1+0+6) (or 97 + (9+7)).

MATHEMATICA

t={}; Do[p=Prime[n]; c=0; i=1; While[i<p&&c!=1, If[i+Total[IntegerDigits[i]] ==p, c=1; AppendTo[t, p]]; i++], {n, 65}]; t (* Jayanta Basu, May 03 2013 *)

Union[Select[Table[n+Total[IntegerDigits[n]], {n, 400}], PrimeQ]] (* Harvey P. Dale, Jul 14 2014 *)

PROG

(Haskell)

a048521 n = a048521_list !! (n-1)

a048521_list = map a000040 $ filter ((> 0) . a107740) [1..]

-- Reinhard Zumkeller, Sep 27 2014

CROSSREFS

Cf. A007953, A047791, A048520.

Cf. A006378, A062028, A107741.

Cf. A000040, A107740, A049084.

Sequence in context: A113626 A154539 A137238 * A172071 A058048 A241659

Adjacent sequences:  A048518 A048519 A048520 * A048522 A048523 A048524

KEYWORD

nonn,base

AUTHOR

Patrick De Geest, May 15 1999.

EXTENSIONS

Formula and also offset corrected by Reinhard Zumkeller, Sep 27 2014

STATUS

approved

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Last modified April 23 18:34 EDT 2019. Contains 322387 sequences. (Running on oeis4.)