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A062337 Primes whose sum of digits is 7. 7
7, 43, 61, 151, 223, 241, 313, 331, 421, 601, 1033, 1051, 1123, 1213, 1231, 1303, 1321, 2113, 2131, 2203, 2221, 2311, 3121, 3301, 4003, 4021, 4111, 4201, 5011, 5101, 10141, 10303, 10321, 10501, 11113, 11131, 11311, 12211, 12301, 13003, 14011 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

There are O((log n)^6) members of this sequence below n.

LINKS

Charles R Greathouse IV, Table of n, a(n) for n=1..10000

EXAMPLE

601 is a prime with sum of the digits = 7, hence belongs to the sequence.

MATHEMATICA

Select[Prime[Range[3000]], Plus @@ IntegerDigits[ # ] == 7 &] (Zak Seidov, Feb 17 2005)

PROG

(PARI) A062337(lim)={my(pow=ceil(log(floor(lim)-.5)/log(10)), n); print("Checking for members of A062337 up to 10^"pow); for(a=0, pow-1, for(b=0, a, for(c=0, b, for(d=0, c, for(e=0, d, for(f=0, e, n=10^a+10^b+10^c+10^d+10^e+10^f+1; if(isprime(n), print1(n", "))))))))};

(PARI) SumD(x)= { s=0; while (x>9, s+=x-10*(x\10); x\=10); return(s + x) } { default(primelimit, 2*10^8); n=0; forprime (p=2, 2*10^8, if (SumD(p) == 7, write("b062337.txt", n++, " ", p); if (n==500, break)) ) } \\ [Harry J. Smith, Aug 05 2009]

(MAGMA) [p: p in PrimesUpTo(250000) | &+Intseq(p) eq 7]; // Vincenzo Librandi, Jul 08 2014

CROSSREFS

Subsequence of A062336. See also A000579.

Cf. similar sequences listed in A244918.

Sequence in context: A085704 A243459 A061241 * A176252 A118703 A139832

Adjacent sequences:  A062334 A062335 A062336 * A062338 A062339 A062340

KEYWORD

nonn,base,easy

AUTHOR

Amarnath Murthy, Jun 21 2001

EXTENSIONS

More terms from Larry Reeves (larryr(AT)acm.org), Jul 06 2001

Comments and program from Charles R Greathouse IV, Sep 11 2009

STATUS

approved

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Last modified June 29 03:09 EDT 2017. Contains 288858 sequences.