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A156294 Sum of products of the digits of prime numbers and the position of the digits in the prime numbers. 1
2, 3, 5, 7, 3, 7, 15, 19, 8, 20, 5, 17, 6, 10, 18, 11, 23, 8, 20, 9, 13, 25, 14, 26, 23, 4, 10, 22, 28, 12, 26, 10, 28, 34, 36, 14, 32, 22, 34, 24, 42, 20, 22, 28, 40, 46, 7, 15, 27, 33, 17, 35, 13, 15, 33, 23, 41, 19, 37, 21, 27, 29, 24, 8, 14, 26, 12, 30, 32, 38, 22, 40, 36, 26, 44 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Indranil Ghosh, Table of n, a(n) for n = 1..50000

FORMULA

a(n) = A156207(prime(n)). - R. J. Mathar, Sep 10 2016

EXAMPLE

For n = 5, prime(5) = 11 and A156207(11) = 1*1 + 1*2 = 3. So, a(5) = 3. - Indranil Ghosh, Feb 11 2017

MATHEMATICA

Table[Total[IntegerDigits[#] Range@ IntegerLength@ #] &@ Prime@ n, {n, 75}] (* Michael De Vlieger, Feb 11 2017 *)

PROG

(PARI) g(x) = local(v, j); v=Vec((Str(x))); sum(j=1, length(v), j*eval(v[j]))

g1(n) = local(j); forprime(j=1, n, print1(g(j)", "))

CROSSREFS

Sequence in context: A239037 A126050 A163821 * A126607 A124322 A209037

Adjacent sequences:  A156291 A156292 A156293 * A156295 A156296 A156297

KEYWORD

base,nonn

AUTHOR

Cino Hilliard, Feb 07 2009

STATUS

approved

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Last modified October 19 13:01 EDT 2019. Contains 328222 sequences. (Running on oeis4.)