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A106721 Largest of seven consecutive primes whose sum of digits is prime. 1
3301, 3307, 4201, 4441, 4447, 14347, 14369, 14387, 27127, 27143, 34259, 67217, 102121, 103069, 106181, 106187, 110647, 200159, 200171, 200177, 210097, 210101, 210109, 231827, 243109, 250147, 302941, 314641, 388903, 402223, 431807, 550061 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..2000

EXAMPLE

a(1)=3301 is a term because this is Largest of seven consecutive primes i.e. 3251,3253,3257,3259,3271,3299 and 3301, whose sum of digits is prime i.e. 3+2+5+1=11, 3+2+5+3=13, 3+2+5+7=17, 3+2+5+9=19, 3+2+7+1=13, 3+2+9+9=23 and 3+3+0+1=7.

MATHEMATICA

sdpQ[pr_]:=AllTrue[Total[IntegerDigits[#]]&/@pr, PrimeQ]; Transpose[Select[ Partition[ Prime[ Range[50000]], 7, 1], sdpQ]][[7]] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Jan 09 2015 *)

CROSSREFS

Sequence in context: A242862 A078951 A236660 * A078969 A320717 A106724

Adjacent sequences:  A106718 A106719 A106720 * A106722 A106723 A106724

KEYWORD

base,nonn

AUTHOR

Shyam Sunder Gupta, May 14 2005

STATUS

approved

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Last modified January 19 18:25 EST 2020. Contains 331051 sequences. (Running on oeis4.)