A042939 - OEIS

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A042939

Absolute values between digits of primes.

2, 3, 5, 7, 0, 2, 6, 8, 1, 7, 2, 4, 3, 1, 3, 2, 4, 5, 1, 6, 4, 2, 5, 1, 2, 0, 2, 6, 8, 3, 8, 3, 9, 11, 12, 5, 11, 8, 12, 9, 15, 8, 9, 11, 15, 17, 0, 3, 7, 9, 4, 10, 3, 4, 10, 7, 13, 6, 12, 7, 9, 10, 4, 1, 1, 5, 1, 7, 8, 10, 5, 11, 10, 7, 13, 8, 14, 13, 3, 5, 6, 1, 0, 2, 8, 3, 9, 8, 3, 5, 9, 12, 11, 6

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OFFSET

1,1

COMMENTS

a(n) = absolute difference between the first digit of prime(n) and the sum of the other digits of prime(n). [Harvey P. Dale, Mar 11 2012]

LINKS

James Spahlinger, Table of n, a(n) for n = 1..10000

FORMULA

If decimal expansion of n-th prime is x1 x2 x3......xk then a(n)=|x1-x2-x3.......-xk|

a(n) = A040997(A000040(n)). - Reinhard Zumkeller, Oct 10 2012

MATHEMATICA

ddp[n_]:=Module[{idn=IntegerDigits[n]}, Abs[First[idn]-Total[Rest[idn]]]]; ddp/@Prime[Range[100]] (* Harvey P. Dale, Mar 11 2012 *)