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A061077 Sum of the products of the digits of the first n odd numbers. 1
1, 4, 9, 16, 25, 26, 29, 34, 41, 50, 52, 58, 68, 82, 100, 103, 112, 127, 148, 175, 179, 191, 211, 239, 275, 280, 295, 320, 355, 400, 406, 424, 454, 496, 550, 557, 578, 613, 662, 725, 733, 757, 797, 853, 925, 934, 961, 1006, 1069, 1150, 1150, 1150, 1150 (list; graph; refs; listen; history; internal format)
OFFSET

0,2

COMMENTS

The limit of the diagonals is A000712 (partitions into parts of two kinds). In particular, if 0<=m<=n, T(n(n+1)/2 + m, n) = A000712(m). These partitions in this range can be viewed as an equilateral right triangle of side n, with one partition appended on the top (at the left) and another appended on the right. - Frank Adams-Watters (FrankTAW(AT)Netscape.net), Jan 11 2006

REFERENCES

Amarnath Murthy, Smarandache friendly numbers and a few more sequences, Smarandache Notions Journal, Vol. 12, No. 1-2-3, Spring 2001.

LINKS

Matthew M. Conroy, Home page (listed instead of email address)

M. L. Perez et al., eds., Smarandache Notions Journal

FORMULA

a(n) = Sum_{k = 1..n} product of the digits of 2k+1.

EXAMPLE

a(7) = 1+3+5+7+9+1x1+1x3 = 29

CROSSREFS

Cf. A061076, A061078.

Sequence in context: A017668 A074373 A067115 * A086132 A010433 A175592

Adjacent sequences:  A061074 A061075 A061076 * A061078 A061079 A061080

KEYWORD

nonn,base,easy

AUTHOR

Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Apr 14 2001

EXTENSIONS

More terms from Matthew M. Conroy, Apr 16 2001

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Last modified February 15 20:26 EST 2012. Contains 205852 sequences.