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A165459 Primes p such that the sum of the digits of p^2 is 16. 5
13, 23, 31, 41, 59, 103, 131, 139, 211, 229, 239, 347, 401, 491, 499, 571, 751, 1021, 1201, 1229, 1453, 1489, 1499, 1741, 2003, 2011, 3001, 3821, 4001, 4639, 4649, 5701, 7079, 8951, 10111, 10247, 10301, 10499, 14251, 14639, 16249, 17321, 19751, 20011 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..80

FORMULA

{A000040(i) : A123157(i) = 16}. [R. J. Mathar, Nov 09 2009]

EXAMPLE

31 is in the sequence because 31^2=961 and 9+6+1=16;

1489 is in the sequence because 1489^2=2217121 and 2+2+1+7+1+2+1=16;

3001 is in the sequence because 3001^2=9006001 and 9+0+0+6+0+0+1=16.

MAPLE

A007953 := proc(n) local d ; add(d, d=convert(n, base, 10)) ; end proc: A165459 := proc(n) local a ; if n = 1 then 13; else a := nextprime( procname(n-1)) ; while A007953(a^2) <> 16 do a := nextprime(a) ; end do ; return a ; end if; end proc: seq(A165459(n), n=1..50) ; # R. J. Mathar, Nov 09 2009

MATHEMATICA

Select[Prime[Range[3000]], Total[IntegerDigits[#^2]]==16 &] (* Vincenzo Librandi, Jun 24 2013 *)

PROG

(MAGMA) [p: p in PrimesUpTo(3*10^4) | &+Intseq(p^2) eq 16]; // Bruno Berselli, Jun 24 2013

CROSSREFS

Sequence in context: A342253 A296806 A143788 * A108794 A272721 A089777

Adjacent sequences:  A165456 A165457 A165458 * A165460 A165461 A165462

KEYWORD

nonn,less,base

AUTHOR

Vincenzo Librandi, Sep 20 2009

EXTENSIONS

Edited by N. J. A. Sloane, Sep 25 2009

347 inserted, more terms added by R. J. Mathar, Nov 09 2009

STATUS

approved

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Last modified May 14 18:54 EDT 2021. Contains 343900 sequences. (Running on oeis4.)