A156979 - OEIS

A156979

Primes p such that 1 = abs(largest digit of p - sum of all the other digits of p).

23, 43, 67, 89, 113, 131, 157, 179, 197, 199, 223, 241, 263, 269, 311, 313, 331, 337, 353, 359, 373, 379, 397, 421, 449, 461, 463, 571, 593, 607, 641, 643, 661, 683, 719, 733, 739, 751, 809, 827, 829, 863, 881, 919, 937, 953, 971, 991, 1013, 1031, 1033

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..5000

EXAMPLE

If prime=197(1<7<9) and 1=abs(9-(1+7)), then 197=a(10). If prime=199(1<9=9) and 1=abs(9-(9+1)), then 199=a(11). If prime=223(2=2<3) and 1=abs(3-(2+2)), then 223=a(12), etc.

MAPLE

From R. J. Mathar, Mar 18 2010: (Start)

A007953 := proc(n) local d ; add(d, d= convert(n, base, 10)) ; end proc:

A054055 := proc(n) local d ; max(op(convert(n, base, 10))) ; end proc:

isA156979 := proc(n) isprime(n) and abs(A007953(n)-2*A054055(n)) = 1 ; end proc:

for n from 1 to 1050 do if isA156979(n) then printf("%d, ", n); end if; end do: (End)

MATHEMATICA

ldodQ[n_]:=Module[{sidn=Sort[IntegerDigits[n]]}, Abs[Total[Most[ sidn]]- Last[ sidn]] == 1]; Select[Prime[Range[200]], ldodQ] (* Harvey P. Dale, Nov 13 2013 *)

CROSSREFS

Cf. A000040, A040997.

Sequence in context: A037137 A340136 A154530 * A281226 A158283 A155786

Adjacent sequences: A156976 A156977 A156978 * A156980 A156981 A156982

KEYWORD

nonn,base

AUTHOR

Juri-Stepan Gerasimov, Feb 20 2009

STATUS

approved