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A173798 Partial sums of A030467. 0
428, 1001, 1728, 2574, 10384, 46749, 110385, 437119, 1110386, 5655840, 11110387, 58169210, 111110388, 443094195, 775761529, 1160376915, 1583539808, 2059064285, 2583539809, 3160646912, 3776031527, 4443364194, 5111380388 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Partial sums of numbers n such that n^2 is a concatenation of two successive numbers (base 10).

LINKS

Table of n, a(n) for n=1..23.

FORMULA

a(n) = SUM[i=1..n] A030467(i) = SUM[i=1..n] {k such that k^2 = concatenation(j, j+1) for some j}.

EXAMPLE

a(15) = 428 + 573 + 727 + 846 + 7810 + 36365 + 63636 + 326734 + 673267 + 4545454 + 5454547 + 47058823 + 52941178 + 331983807 + 332667334 = 775761529 is prime.

CROSSREFS

Cf. A030467, A030465, A030466, A054214, A054215, A054216, A020339, A020340.

Sequence in context: A224668 A030467 A253505 * A233812 A231047 A177328

Adjacent sequences:  A173795 A173796 A173797 * A173799 A173800 A173801

KEYWORD

base,nonn

AUTHOR

Jonathan Vos Post, Feb 25 2010

STATUS

approved

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Last modified November 14 20:15 EST 2019. Contains 329130 sequences. (Running on oeis4.)