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A111101 Cumulative sum of A000001(n)^A000001(n). 0
1, 2, 3, 7, 8, 12, 13, 3138, 3142, 3146, 3147, 6272, 6273, 6277, 6278, 11112006825564294, 11112006825564295, 11112006825567420, 11112006825567421, 11112006825570546, 11112006825570550 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

a(n) is prime for n = 2, 3, 4, 7, 14. a(n) is semiprime for n = 9, 11, 18, 26.

LINKS

Table of n, a(n) for n=1..21.

FORMULA

a(n) = Sum[from i to n] A000001(i)^A000001(i).

EXAMPLE

a(7) = 1^1 + 1^1 + 1^1 + 2^2 + 1^1 + 2^2 + 1^1 = 13, which is prime.

a(14) = 1^1 + 1^1 + 1^1 + 2^2 +1^1 + 2^2 + 1^1 + 5^5 + 2^2 + 2^2+ 1^1 + 5^5 + 1^1 + 2^2 = 6277, which is prime.

a(29) = 1^1 + 1^1 + 1^1 + 2^2 + 1^1 + 2^2 + 1^1 + 5^5 + 2^2 + 2^2+ 1^1 + 5^5 + 1^1 + 2^2 + 1^1 + 14^14 + 1^1 + 5^5 + 1^1 + 5^5 + 2^2 + 2^2 + 1^1 + 15^15 + 2^2 + 2^2 + 5^5 + 4^4 + 1^1 = 449005897206433320.

CROSSREFS

Cf. A000001.

Sequence in context: A233998 A047221 A032967 * A281017 A281018 A184860

Adjacent sequences:  A111098 A111099 A111100 * A111102 A111103 A111104

KEYWORD

easy,nonn

AUTHOR

Jonathan Vos Post, Oct 13 2005

STATUS

approved

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Last modified August 23 22:45 EDT 2019. Contains 326254 sequences. (Running on oeis4.)