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A061787
a(n) = Sum_{k=1..n} (2k-1)^(2k-1).
3
1, 28, 3153, 826696, 388247185, 285699917796, 303160806510049, 438197051187369424, 827678458937524133601, 1979247334119251113257580, 5844566265720101772494382001, 20886312566113632136127527292568
OFFSET
1,2
LINKS
FORMULA
a(n) ~ exp(-1) * 2^(2*n-1) * n^(2*n-1). - Vaclav Kotesovec, Dec 09 2021
EXAMPLE
a(3) = 1 + 3^3 + 5^5 = 3153.
MATHEMATICA
Array[Sum[(2 k - 1)^(2 k - 1), {k, #}] &, 12] (* Michael De Vlieger, Jul 01 2018 *)
Accumulate[#^#&/@Range[1, 25, 2]] (* Harvey P. Dale, Jul 16 2022 *)
PROG
(PARI) { a=n=0; forstep (p=1, 200, 2, write("b061787.txt", n++, " ", a+=p^p) ) } \\ Harry J. Smith, Jul 28 2009
(GAP) List([1..13], n->Sum([1..n], k->(2*k-1)^(2*k-1))); # Muniru A Asiru, Jul 01 2018
CROSSREFS
Partial sums of A085529.
Sequence in context: A277657 A285151 A232520 * A235458 A128506 A164655
KEYWORD
nonn,easy
AUTHOR
Amarnath Murthy, May 25 2001
EXTENSIONS
Corrected and extended by Jason Earls, May 27 2001
STATUS
approved