OFFSET
1,1
REFERENCES
J. R. Smart, A new function from a table of primes, J. Rec. Math., 7 (No. 4, 1974), 293-294.
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
LINKS
Reinhard Zumkeller, Table of n, a(n) for n = 1..10000
J. R. Smart, A new function from a table of primes, J. Recreational Mathematics 7.4 (1974), 293-294. (Annotated scanned copy)
EXAMPLE
523 and 541 are first pair of consecutive primes with same sum of digits (10).
MAPLE
MATHEMATICA
prms=Prime[Range[2000]]; First/@Table[First[Select[Partition[prms, n, 1], Total[ IntegerDigits[ First[#]]]==Total[IntegerDigits[Last[#]]]&]], {n, 75}] (* Harvey P. Dale, May 20 2011 *)
PROG
(Haskell)
import Data.Function (on)
import Data.List (elemIndex)
import Data.Maybe (fromJust)
a007513 n = a000040_list !! (fromJust $ elemIndex 0 $
zipWith ((-) `on` a007953) a000040_list $ drop (n-1) a000040_list)
-- Reinhard Zumkeller, Aug 17 2011
CROSSREFS
KEYWORD
AUTHOR
EXTENSIONS
Terms beyond a(57) by R. J. Mathar, Dec 09 2009
STATUS
approved