A111380 -id:A111380 - cp's OEIS frontend

A181321 Primes with digital sum 70.

189997999, 199799989, 199898899, 199997899, 199997989, 199998889, 268999999, 269998999, 278989999, 278999989, 279889999, 279988999, 287998999, 287999989, 288998989, 288999889, 288999979, 289699999, 289789999, 289889989

Offset: 1

Zak Seidov, Jan 26 2011

The sequence begins with 8438 9-digit numbers.
Then there are 739572 10-digit numbers.
All terms == 7 (mod 18).

T. D. Noe, Table of n, a(n) for n = 1..8438

Cf. A073867, A111380, A181178, A181182.

Cf. similar sequences listed in A244918.

[p: p in PrimesUpTo(3*10^8) | &+Intseq(p) eq 70]; // Vincenzo Librandi, Jul 09 2014

Select[Prime[Range[3*10^8]], Total[IntegerDigits[#]]==70 &] (* Vincenzo Librandi, Jul 09 2014 *)

# see code in A107579 which can be used to produce this sequence by giving the initial term p = 189997999 (or 8*10**7-1, for digit sum 70). - M. F. Hasler, Mar 16 2022

A152652 Least prime p with digit sum A047235(n).

Original entry on oeis.org

2, 13, 17, 19, 59, 79, 389, 499, 1889, 1999, 6899, 17989, 39989, 49999, 98999, 199999, 599999, 799999, 2999999, 4999999, 9899999, 19999999, 59999999, 189997999, 389999999, 689899999, 998999999, 2999899999, 6999999989, 9899989999, 39899999999, 68899999999, 98999999999

Offset: 1

Giovanni Teofilatto, Dec 10 2008

David A. Corneth, Table of n, a(n) for n = 1..1713

Cf. A111380 (smallest prime whose digital sum is equal to the n-th composite number not congruent to 0 (modulo 3)). - Klaus Brockhaus, Dec 12 2008

Cf. A000040, A007605, A047234, A047235.

T:=[ n eq 1 select 2 else Self(n-1)+2*(1+n mod 2): n in [1..22] ]; S:=[]; p:=2; for k in T do while &+Intseq(p, 10) ne k do p:=NextPrime(p); end while; Append(~S,p); end for; S; // Klaus Brockhaus, Dec 13 2008

a(n) = {n = (n-1)\2*6+3+(-1)^n ; t = ceil(n/9); leastfound = oo; while(leastfound == oo, my(p = partitions(n, [1,9], [t,t])); v = vector(#p, i, oo); for(i = 1, #p, if(fromdigits(Vec(p[i])) > leastfound, next(2)); forperm(Vec(p[i]), q, if(isprime(fromdigits(Vec(q))), leastfound = min(leastfound, fromdigits(Vec(q))); v[i] = min(v[i], fromdigits(Vec(q))); next(2); ) ) ); t++ ); leastfound }\\ David A. Corneth, Jun 13 2020

{min A000040(i): A007605(i) = A047234(n)}. - R. J. Mathar, Dec 12 2008

Edited and extended by R. J. Mathar, Dec 12 2008
a(20)-a(22) from Klaus Brockhaus, Dec 13 2008
More terms from Jinyuan Wang, Jun 13 2020

cp's OEIS Frontend

A181321 Primes with digital sum 70.

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